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Biocatalytic oxidations are an emerging technology for selective C-H bond activation. While promising for a range of selective oxidations, practical use of enzymes catalyzing aerobic hydroxylation is presently limited by their substrate scope and stability under industrially relevant conditions. Here, we report the engineering and practical application of a non-heme iron and α-ketoglutarate-dependent dioxygenase for the direct stereo- and regio-selective hydroxylation of a non-native fluoroindanone en route to the oncology treatment belzutifan, replacing a five-step chemical synthesis with a direct enantioselective hydroxylation. Mechanistic studies indicated that formation of the desired product was limited by enzyme stability and product overoxidation, with these properties subsequently improved by directed evolution, yielding a biocatalyst capable of >15,000 total turnovers. Highlighting the industrial utility of this biocatalyst, the high-yielding, green, and efficient oxidation was demonstrated at kilogram scale for the synthesis of belzutifan., (© 2024 Wiley-VCH GmbH.)

The gap between how health information is communicated and what people understand and can use to make informed health decisions is called health literacy. This gap was exacerbated by the rapidly changing and excessive volume of information, misinformation, and disinformation during the COVID-19 pandemic. People with lower health literacy may not have understood the importance of COVID-19 vaccination for themselves or for their communities. Our aim was to understand health literacy levels within Fulton County, Georgia, and their relationship to vaccine prevalence. Fulton county residents ages 18 and over (n = 425) completed an on-line Health Literacy Questionnaire. Individual, organizational, functional, interactive, and critical health literacy scales were created. Vaccination prevalence data were collected from the Georgia Vaccine Distribution Dashboard. All data were divided into one of three county areas. There were statistically significant variations in vaccine prevalence χ2(3) = 29.325, p < 0.001 among the three county areas. All levels of health literacy predicted overall county vaccination prevalence F (4,420) = 85.941, p < 0.001, There were significant differences in health literacy levels among two of the three county area pairs; the lowest resourced county area had the lowest vaccination prevalence and health literacy rates. This is the first example of relating direct health literacy measures across a major metropolitan US county with vaccine prevalence data.

Background: Population-level estimates of sexual network mixing for parameterizing prediction models of pre-exposure prophylaxis (PrEP) effectiveness are needed to inform prevention of HIV transmission among men who have sex with men (MSM). Estimates obtained by egocentric sampling are vulnerable to information bias due to incomplete respondent knowledge., Methods: We estimated patterns of serosorting and PrEP sorting among MSM in the United States using data from a 2017-2019 egocentric sexual network study. Respondents served as proxies to report the HIV status and PrEP use of recent sexual partners. We contrasted results from a complete-case analysis (unknown HIV and PrEP excluded) versus a bias analysis with respondent-reported data stochastically reclassified to simulate unobserved self-reported data from sexual partners., Results: We found strong evidence of preferential partnering across analytical approaches. The bias analysis showed concordance between sexual partners of HIV diagnosis and PrEP use statuses for MSM with diagnosed HIV (39%; 95% simulation interval: 31, 46), MSM who used PrEP (32%; 21, 37), and MSM who did not use PrEP (83%; 79, 87). The fraction of partners with diagnosed HIV was higher among MSM who used PrEP (11%; 9, 14) compared with MSM who did not use PrEP (4%; 3, 5). Comparatively, across all strata of respondents, the complete-case analysis overestimated the fractions of partners with diagnosed HIV or PrEP use., Conclusions: We found evidence consistent with HIV and PrEP sorting among MSM, which may decrease the population-level effectiveness of PrEP. Bias analyses can improve mixing estimates for parameterization of transmission models., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Molnupiravir (MK-4482) is an investigational antiviral agent that is under development for the treatment of COVID-19. Given the potential high demand and urgency for this compound, it was critical to develop a short and sustainable synthesis from simple raw materials that would minimize the time needed to manufacture and supply molnupiravir. The route reported here is enabled through the invention of a novel biocatalytic cascade featuring an engineered ribosyl-1-kinase and uridine phosphorylase. These engineered enzymes were deployed with a pyruvate-oxidase-enabled phosphate recycling strategy. Compared to the initial route, this synthesis of molnupiravir is 70% shorter and approximately 7-fold higher yielding. Looking forward, the biocatalytic approach to molnupiravir outlined here is anticipated to have broad applications for streamlining the synthesis of nucleosides in general., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Seroadaptive behaviors help reduce HIV risk for some men who have sex with men (MSM), and have been well documented across MSM populations. Advancements in biomedical prevention have changed the contexts in which seroadaptive behaviors occur. We thus sought to estimate and compare the prevalence of four stages of the "seroadaptive cascade" by PrEP use in the recent era: knowledge of own serostatus, knowledge of partner serostatus; serosorting (matching by status), and condomless anal intercourse. Serosorting overall appeared to remain common, especially with casual and one-time partners. Although PrEP use did not impact status discussion, it did impact serosorting and the likelihood of having condomless anal intercourse. For respondents not diagnosed with HIV and not on PrEP, condomless anal intercourse occurred in just over half of relationships with HIV-positive partners who were not on treatment. Biomedical prevention has intertwined with rather than supplanted seroadaptive behaviors, while contexts involving neither persist., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In the past decade, the field of organic synthesis has witnessed tremendous advancements in the areas of photoredox catalysis, electrochemistry, C-H activation, reductive coupling and flow chemistry. While these methods and technologies offer many strategic advantages in streamlining syntheses, their application on the process scale is complicated by several factors. In this Review, we discuss the challenges that arise when these reaction classes and/or flow chemistry technology are taken from a research laboratory operating at the milligram scale to a reactor capable of producing kilograms of product. We discuss how these challenges have been overcome through chemical and engineering solutions. Specifically, this Review will highlight key examples that have led to the production of multi-hundred-gram to kilogram quantities of active pharmaceutical ingredients or their intermediates and will provide insight on the scaling-up process to those developing new technologies and reactions., (© 2021. Springer Nature Limited.)

Background: Long-acting injectable (LAI) human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) is reportedly efficacious, although full trial results have not been published. We used a dynamic network model of HIV transmission among men who have sex with men to assess the population impact of LAI-PrEP when available concurrently with daily-oral (DO) PrEP., Methods: The reference model represents the current HIV epidemiology and DO-PrEP coverage (15% among those with behavioral indications for PrEP) among men who have sex with men in the southeastern United States. Primary analyses investigated varied PrEP uptake and proportion selecting LAI-PrEP. Secondary analyses evaluated uncertainty in pharmacokinetic efficacy and LAI-PrEP persistence relative to DO-PrEP., Results: Compared with the reference scenario, if 50% chose LAI-PrEP, 4.3% (95% simulation interval, -7.3% to 14.5%) of infections would be averted over 10 years. The impact of LAI-PrEP is slightly greater than that of the DO-PrEP-only regimen, based on assumptions of higher adherence and partial protection after discontinuation. If the total PrEP initiation rate doubled, 17.1% (95% simulation interval, 6.7%-26.4%) of infections would be averted. The highest population-level impact occurred when LAI-PrEP uptake and persistence improved., Conclusions: If LAI-PrEP replaces DO-PrEP, its availability will modestly improve the population impact. LAI-PrEP will make a more substantial impact if its availability drives higher total PrEP coverage, or if persistence is greater for LAI-PrEP., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

A 5-step enantioselective synthesis of the potent anti-HIV nucleoside islatravir is reported. The highly efficient route was enabled by a novel enantioselective alkynylation of an α,β-unsaturated ketone, a unique ozonolysis-dealkylation cascade in water, and an enzymatic aldol-glycosylation cascade., (© 2020 Wiley-VCH GmbH.)

Bruton's tyrosine kinase (BTK) is a Tec family kinase with a well-defined role in the B cell receptor (BCR) pathway. It has become an attractive kinase target for selective B cell inhibition, and for the treatment of B cell related diseases. Many BTK inhibitors have been discovered for the treatment of cancer and rheumatoid arthritis, including a series of BTK inhibitors based on 8-amino-imidazo[1,5-a]pyrazine we recently reported. The X-ray crystal structures of BTK with inhibitors were also published, which provided great help for the SAR design. Here we report our SAR work introducing ring constraints for the 3-position piperidine amides on the BTK inhibitors based on 8-amino-imidazo[1,5-a]pyrazine. This modification improved the potency in BTK inhibitions, as well as the PK profile and the off-target selectivity. The dose-dependent efficacy of two BTK inhibitors was observed in the rat collagen induced arthritis (CIA) model., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The synthesis of the potent anti-HIV investigational treatment islatravir is described. The key step in this synthesis is a highly enantioselective catalytic asymmetric alkynylation of a ketone. This reaction is a rare example of the asymmetric addition of an alkyne nucleophile to a ketone through ligand-accelerated catalysis that was performed on a greater than 100 g scale. By leveraging a multienzyme cascade, a highly diastereoselective aldol-glycosylation was used to complete the target in eight steps.

Amphetamine use is higher among men who have sex with men (MSM) compared with other men, and is associated with sexual behavior linked to HIV transmission. No national estimates of amphetamine use among MSM with HIV have been published. We used data from the Medical Monitoring Project, a nationally representative sample of persons with diagnosed HIV, to describe patterns in amphetamine use in the past 12 months among MSM during 2015-2016 (N = 3796). Prevalence of amphetamine use in this population was 9.6% (95% CI 7.6, 11.6%) in the past 12 months. MSM who used amphetamines were more likely to have condomless sex with partners without HIV or of unknown serostatus (PR 1.87; 95% CI 1.62, 2.16) and less likely to be durably virally suppressed (PR 0.81; 95% CI 0.71, 0.91). Interventions to address amphetamine use and associated transmission risk behaviors among MSM living with HIV may decrease transmission.

Introduction: Electronic and other new media technologies (eHealth) can facilitate large-scale dissemination of information and effective delivery of interventions for HIV care and prevention. There is a need to both monitor a rapidly changing pipeline of technology-based care and prevention methods and to assess whether the interventions are appropriately diversified. We systematically review and critically appraise the research pipeline of eHealth interventions for HIV care and prevention, including published studies and other funded projects., Methods: Two peer-reviewed literature databases were searched for studies describing the development, trial testing or implementation of new technology interventions, published from September 2014 to September 2018. The National Institutes of Health database of grants was searched for interventions still in development. Interventions were included if eHealth was utilized and an outcome directly related to HIV treatment or prevention was targeted. We summarized each intervention including the stage of development, eHealth mode of delivery, target population and stage of the HIV care and prevention continua targeted., Results and Discussion: Of 2178 articles in the published literature, 113 were included with 84 unique interventions described. The interventions utilize a variety of eHealth technologies and target various points on the prevention and care continua, with greater emphasis on education, behaviour change and testing than linkage to medical care. There were a variety of interventions for HIV care support but none for PrEP care. Most interventions were developed for populations in high income countries. An additional 62 interventions with funding were found in the development pipeline, with greater emphasis on managing HIV and PrEP care., Conclusions: Our systematic review found a robust collection of eHealth interventions in the published literature as well as unpublished interventions still in development. In the published literature, there is an imbalance of interventions favouring education and behaviour change over linkage to care, retention in care, and adherence, especially for PrEP. The next generation of interventions already in the pipeline might address these neglected areas of care and prevention, but the development process is slow. Researchers need new methods for more efficient and expedited intervention development so that current and future needs are addressed., (© 2020 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Insulin oligosaccharide conjugates hold promise as potential glucose-responsive insulins (GRIs), which can improve the therapeutic index of insulins and mitigate the risk of hypoglycemia. A key challenge for the analytical development of such molecules is finding an efficient method to characterize the purity and impurities of conjugated insulins. Using the S-Matrix Fusion QbD-ultrahigh performance liquid chromatography (UHPLC) integrated system, we were able to quickly screen and develop two short UHPLC methods. These methods were used to support process development, clinical batch drug substance (DS) release, and stability studies of MK-2640, an insulin oligosaccharide conjugate. Both methods used a Waters CSH C18 column, with a shallow gradient of acetonitrile to aqueous mobile phase containing 25 mM sodium perchlorate and 0.05% perchloric acid. The 10-min run time method was well suited for process development and monitoring as it was able to separate the main product, MK-2640, six oligosaccharide-substituted recombinant human insulin (RHI) impurities, A21 deamidated MK-2640, and the starting material RHI. The 13-min run time method provided improved separation of the major impurities and demonstrated good chromatographic reproducibility on different instruments or using columns from different lots of stationary phase, which made it ideal for the final DS release. Validation of the 13-min method demonstrated great linearity for both the MK-2640 main peak and its related impurities, low limit of detection (0.02%), and limit of quantitation (0.05%). The high specificity of the method allowed the separation of the degradation products from main peak, thus makes it suitable for stability monitoring. The major impurities in the DS were characterized by two-dimensional liquid chromatography-mass spectrometry (2D-LC-MS).

Enzyme-catalyzed reactions have begun to transform pharmaceutical manufacturing, offering levels of selectivity and tunability that can dramatically improve chemical synthesis. Combining enzymatic reactions into multistep biocatalytic cascades brings additional benefits. Cascades avoid the waste generated by purification of intermediates. They also allow reactions to be linked together to overcome an unfavorable equilibrium or avoid the accumulation of unstable or inhibitory intermediates. We report an in vitro biocatalytic cascade synthesis of the investigational HIV treatment islatravir. Five enzymes were engineered through directed evolution to act on non-natural substrates. These were combined with four auxiliary enzymes to construct islatravir from simple building blocks in a three-step biocatalytic cascade. The overall synthesis requires fewer than half the number of steps of the previously reported routes., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Sulfonamides are pervasive in pharmaceuticals and agrochemicals, yet they are typically considered as terminal functional groups rather than synthetic handles. To enable the general late-stage functionalization of secondary sulfonamides, we have developed a mild and general method to reductively cleave the N-S bonds of sulfonamides to generate sulfinates and amines, components which can further react in situ to access a variety of other medicinally relevant functional groups. The utility of this platform is highlighted by the selective manipulation of several complex bioactive molecules.

Clinical guidelines for HIV pre-exposure prophylaxis (PrEP) include risk prediction tools to identify appropriate candidates. We conducted a qualitative interview study to explore the potential acceptability, interpretation, and anticipated impact of such tools from the perspectives of men who have sex with men (MSM) and primary care providers (PCPs). Our purposive sample of English-speaking participants included: (1) MSM reporting HIV risk behaviors ( n  = 32; median age = 38 years; 53% non-Hispanic white; 22% high school degree or less education); (2) PCPs specializing in health care for MSM ( n  = 12); and (3) PCPs in general practice ( n  = 19). MSM participants questioned the ability of risk tools to predict HIV acquisition, and their perceptions of what might constitute a high HIV risk score varied widely. Many MSM participants believed that receiving a high score would prompt them to consider PrEP or other risk reduction strategies. Some believed that the data would be useful, particularly if discussed with their providers, whereas others anticipated feeling fear, anxiety, or mistrust. PCPs expressed more confidence in HIV risk prediction and imagined integrating tools with medical histories and their clinical judgment to assess risk. PCPs were most enthusiastic about adopting HIV risk prediction as a teaching tool to help patients visualize and reduce risk, their concerns about time constraints notwithstanding. In conclusion, our findings suggest that PCPs' views of HIV risk prediction tools are generally positive, whereas MSM participants' are more mixed. Given that both groups emphasized the value of contextualizing risk, shared decision making may be needed to implement HIV risk prediction tools effectively.

Synthetic diazeniumdiolate (DAZD)-based nitric oxide is utilized to modulate the nitric oxide (NO) concentration in cellular environments and to control physiological processes, yet chemists are still struggling to find efficient and scalable methodologies that will enable them to access sufficient quantities of the high-energy diazeniumdiolate intermediates for biological studies. Now, a general, scalable, safer, and high-yielding new methodology adaptable to the large-scale synthesis of DAZDs has been developed.

The potential for human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) to reduce the racial disparities in HIV incidence in the United States might be limited by racial gaps in PrEP care. We used a network-based mathematical model of HIV transmission for younger black and white men who have sex with men (BMSM and WMSM) in the Atlanta, Georgia, area to evaluate how race-stratified transitions through the PrEP care continuum from initiation to adherence and retention could affect HIV incidence overall and disparities in incidence between races, using current empirical estimates of BMSM continuum parameters. Relative to a no-PrEP scenario, implementing PrEP according to observed BMSM parameters was projected to yield a 23% decline in HIV incidence (hazard ratio = 0.77) among BMSM at year 10. The racial disparity in incidence in this observed scenario was 4.95 per 100 person-years at risk (PYAR), a 19% decline from the 6.08 per 100 PYAR disparity in the no-PrEP scenario. If BMSM parameters were increased to WMSM values, incidence would decline by 47% (hazard ratio = 0.53), with an associated disparity of 3.30 per 100 PYAR (a 46% decline in the disparity). PrEP could simultaneously lower HIV incidence overall and reduce racial disparities despite current gaps in PrEP care. Interventions addressing these gaps will be needed to substantially decrease disparities., (Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2019.)

Introduction: Discontinuations of HIV preexposure prophylaxis (PrEP) by at-risk individuals could decrease the effectiveness of PrEP. Our objective was to characterize patterns of, reasons for, and clinical outcomes associated with PrEP discontinuations in primary care., Methods: We conducted medical chart reviews for patients prescribed PrEP during 2011 to 2014 at a Boston community health centre specializing in healthcare for sexual and gender minorities. Patients were followed through 2015. We characterized patients' sociodemographics, relationship status, behavioural health conditions, patterns of and reasons for PrEP discontinuations, and HIV seroconversions. Cox proportional hazards models were used to assess patient factors associated with PrEP discontinuations., Results: Of the 663 patients prescribed PrEP, the median age was 33 years, 96% were men who have sex with men (MSM) and 73% were non-Hispanic white; 40% were in committed relationships and 15% had HIV-infected partners. Patients either used PrEP continuously (60%), had 1 or more discontinuations (36%), or did not initiate PrEP (4%). Discontinuations were most often due to a decrease in HIV risk perception (33%), non-adherence to care plans (16%), or insurance barriers (12%). Of the 7 (1.1%) PrEP patients diagnosed with HIV, 1 was HIV-infected at baseline, 2 seroconverted while using PrEP, and 4 seroconverted after discontinuations. In a multivariable model adjusted for race/ethnicity, relationship status, substance use disorders, and insurance status, those who were less than 30 years old (aHR 2.0, 95% CI 1.4 to 2.9 for ages 18 to 24, aHR 2.2, 95% CI 1.6 to 3.1 for ages 25 to 29, vs. ages 30 to 39 years), who identified as transgender women (aHR 2.0, 95% CI 1.2 to 3.4, vs. cisgender men), and who had mental health disorders (aHR 1.2, 95% CI 1.1 to 1.4 for each additional disorder) were more likely to have discontinuations., Conclusions: Discontinuations of PrEP use among this American sample of predominately MSM were common, particularly among patients who were younger, identified as transgender women, or had behavioural health issues. As HIV seroconversions occurred after discontinuations of PrEP, strategies to prevent inappropriate discontinuations are needed., (© 2019 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Herein we describe the development and application of a method for the mild, late-stage conversion of primary sulfonamides to several other other functional groups. These reactions occur via initial reductive deamination of sulfonamides to sulfinates via an NHC-catalyzed reaction of transiently formed N-sulfonylimines. The method described here is tolerant of nearly all common functional groups, as exemplified by the late-stage derivatization of several complex pharmaceutical compounds. On the basis of the prevalence of sulfonamide-containing drugs and building blocks, we have developed a method to enable sulfonamides to be applied as versatile synthetic handles for synthetic chemsitry.

A novel series of tricyclic tetrahydroquinolines were identified as potent and selective CRTh2 receptor antagonists. The agonism and antagonism switch was achieved through structure-based drug design (SBDD) using a CRTh2 receptor homologue model. The challenge of very low exposures in pharmacokinetic studies was overcome by exhaustive medicinal chemistry lead optimization through focused SAR studies on the tricyclic core. Further optimization resulted in the identification of the preclinical candidate 4-(cyclopropyl((3 aS ,9 R ,9 aR )-7-fluoro-4-(4-(trifluoromethoxy)benzoyl)-2,3,3 a ,4,9,9 a -hexahydro-1 H -cyclopenta[ b ]quinolin-9-yl)amino)-4-oxobutanoic acid ( 15c , MK-8318 ) with potent and selective CRTh2 antagonist activity and a favorable PK profile suitable for once daily oral dosing for potential treatment of asthma., Competing Interests: The authors declare no competing financial interest.

Background: The reasons why bacterial sexually transmitted infections (BSTIs) are increasing in US men who have sex with men (MSM) have not been fully characterized., Methods: An open cohort of MSM accessing medical care at a Boston community health center was used to assess secular trends in BSTI diagnoses. Frequency of infection and the estimated population size were used to calculate diagnosis rates. Poisson models were fit for multivariable analyses., Results: Between 2005 and 2015, 19 232 men had at least 1 clinic visit. Most (72.4%) were white; 6.0% were black, and 6.1% were Latino. Almost half had documented self-report of identifying as gay (42.6%) or bisexual (3.2%). Most had private health insurance (61.7%); 5.4% had Medicare, 4.6% had Medicaid, and 8.4% reported no insurance. Between 2005 and 2015, BSTI diagnoses increased more than 8-fold. In 2015, of 1319 men who were diagnosed with at least 1 BSTI; 291 were diagnosed with syphilis, 554 with gonorrhea (51.4% rectal, 31.0% urogenital), and 679 with chlamydia (69.1% rectal, 34.3% urogenital). In 2015, 22.7% of BSTIs were diagnosed among HIV-infected patients (15.4% of the clinic population), and 32.8% of BSTIs were diagnosed among HIV-uninfected patients using pre-exposure prophylaxis (PrEP; 10.1% of all men in care). In multivariable analyses, age 18 to 24 years, being HIV-infected, using PrEP, being nonwhite, or reporting Medicaid or not reporting having private insurance or Medicare were independently associated with being diagnosed with a new BSTI., Conclusions: Over the past decade, BSTI diagnosis rates increased in HIV-infected and uninfected MSM, with disproportionate increases in PrEP users, racial and ethnic minority MSM, those aged 25 to 34 years, and those without stable health insurance, warranting focused education, screening, and accessible services for these key subpopulations.

Purpose: Men who have sex with men (MSM) experience stigma in healthcare settings, which impedes disclosure of sexual behavior, potentially limiting uptake of preexposure prophylaxis (PrEP). The purpose of this study was to describe the context of this limitation and explore geographical variability., Methods: To understand how discomfort in healthcare settings affects PrEP utilization, we conducted two online focus groups with geographically diverse samples of MSM., Results: Respondents identified primary care providers as preferred sources for PrEP, but potential uptake was limited by barriers to establishing nonjudgmental relationships with these providers., Conclusion: Improved patient-provider communication about sexual behaviors might increase PrEP use among MSM.

The Centers for Disease Control and Prevention estimates that one in four sexually active men who have sex with men (MSM) could decrease their HIV risk by using HIV pre-exposure prophylaxis (PrEP). Because many MSM access healthcare from primary care providers (PCPs), these clinicians could play an important role in providing access to PrEP. Semistructured qualitative interviews were conducted with 31 PCPs in Boston, MA, to explore how they approach decisions about prescribing PrEP to MSM and their experiences with PrEP provision. Purposive sampling included 12 PCPs from an urban community health center specializing in the care of lesbian, gay, bisexual, and transgender persons ("LGBT specialists") and 19 PCPs from a general academic medical center ("generalists"). Analyses utilized an inductive approach to identify emergent themes. Both groups of PCPs approached prescribing decisions about PrEP as a process of informed decision-making with patients. Providers would defer to patients' preferences if they were unsure about the appropriateness of PrEP. LGBT specialists and generalists were at vastly different stages of adopting PrEP into practice. For LGBT specialists, PrEP was a disruptive innovation that rapidly became normative in practice. Generalists had limited experience with PrEP; however, they desired succinct decision-support tools to help them achieve proficiency, because they considered preventive medicine to be central to their professional role. As generalists vastly outnumber LGBT specialists in the United States, interventions to support PrEP provision by generalists could accelerate the scale-up of PrEP for MSM nationally, which could in turn decrease HIV incidence for this priority population.

Parallel synthesis and mass-directed purification of a modular ligand library, high-throughput experimentation, and rational ligand evolution have led to a novel copper catalyst for the synthesis of phenols with a traceless hydroxide surrogate. The mild reaction conditions reported here enable the late-stage synthesis of numerous complex, druglike phenols.

The conversion of aryl halides to phenols under mild reaction conditions is a longstanding and formidable challenge in organic chemistry. Herein, we report the rational design of a broadly applicable Pd-catalyzed method to prepare phenols with benzaldehyde oxime as a hydroxide surrogate. These reactions occur under mildly basic conditions and enable the late-stage hydroxylation of several functionally-dense drug-like aryl halides., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A high-yielding and practical method for the synthesis of phenols from electron-deficient haloarenes and heteroarenes has been developed. The products are formed from acetohydroxamic acid as the hydroxide source via a novel SNAr reaction/Lossen rearrangement sequence. Notably, these reactions employ inexpensive and air-stable reagents, require no special handling, occur under mildly basic conditions, and form products in high yields in the presence of electrophilic and protic functionality. The utility of this methodology is demonstrated by the high-yielding hydroxylation of two base-sensitive complex substrates.

Background: Antiretroviral treatment for HIV-infection before immunologic decline (early ART) and pre-exposure chemoprophylaxis (PrEP) can prevent HIV transmission, but routine adoption of these practices by clinicians has been limited., Methods: Between September and December 2013, healthcare practitioners affiliated with a regional AIDS Education and Training Center in New England were invited to complete online surveys assessing knowledge, beliefs and practices regarding early ART and PrEP. Multivariable models were utilized to determine characteristics associated with prescribing intentions and practices., Results: Surveys were completed by 184 practitioners. Respondent median age was 44 years, 58% were female, and 82% were white. Among ART-prescribing clinicians (61% of the entire sample), 64% were aware that HIV treatment guidelines from the Department of Health and Human Services recommended early ART, and 69% indicated they would prescribe ART to all HIV-infected patients irrespective of immunologic status. However, 77% of ART-prescribing clinicians would defer ART for patients not ready to initiate treatment. Three-fourths of all respondents were aware of guidance from the U.S. Centers for Disease Control and Prevention recommending PrEP provision, 19% had prescribed PrEP, and 58% of clinicians who had not prescribed PrEP anticipated future prescribing. Practitioners expressed theoretical concerns and perceived practical barriers to prescribing early ART and PrEP. Clinicians with higher percentages of HIV-infected patients (aOR 1.16 per 10% increase in proportion of patients with HIV-infection, 95% CI 1.01-1.34) and infectious diseases specialists (versus primary care physicians; aOR 3.32, 95% CI 0.98-11.2) were more likely to report intentions to prescribe early ART. Higher percentage of HIV-infected patients was also associated with having prescribed PrEP (aOR 1.19, 95% CI 1.06-1.34), whereas female gender (aOR 0.26, 95% CI 0.10-0.71) was associated with having not prescribed PrEP., Conclusions: These findings suggest many clinicians have shifted towards routinely recommending early ART, but not PrEP, so interventions to facilitate PrEP provision are needed.

Screening for pharmaceutically viable stability from measurements of thermally induced protein unfolding and short-term accelerated stress underpins much molecule design, selection, and formulation in the pharmaceutical biotechnology industry. However, the interrelationships among intrinsic protein conformational stability, thermal denaturation, and pharmaceutical stability are complex. There are few publications in which predictions from thermal unfolding-based screening methods are examined together with pharmaceutically relevant long-term storage stability performance. We have studied eight developable therapeutic IgG molecules under solution conditions optimized for large-scale commercial production and delivery. Thermal unfolding profiles were characterized by differential scanning calorimetry (DSC) and intrinsic fluorescence recorded simultaneously with static light scattering (SLS). These molecules exhibit a variety of thermal unfolding profiles under common reference buffer conditions and under individually optimized formulation conditions. Aggregation profiles by SE-HPLC and bioactivity upon long-term storage at 5, 25, and 40 °C establish that IgG molecules possessing a relatively wide range of conformational stabilities and thermal unfolding profiles can be formulated to achieve pharmaceutically stable drug products. Our data suggest that a formulation design strategy that increases the thermal unfolding temperature of the Fab transition may be a better general approach to improving pharmaceutical storage stability than one focused on increasing Tonset or Tm of the first unfolding transition.

An asymmetric synthesis of dual orexin receptor antagonist MK-6096 (1) is described. Key steps for the trans-2,5-disubstituted piperidinyl ether fragment include a biocatalytic transamination, a trans-selective Mukaiyama aldol, and a regioselective pyridyl SNAr process. The pyrimidyl benzoic acid was synthesized via a Negishi coupling and a nitrile hydrolysis. Coupling of the two fragments via a catalytic T3P-mediated amidation completed the synthesis. Unusual behaviors in the hydrolysis of pyrimidyl benzonitrile and the amide coupling of the pyrimidyl benzoic acid are also described.

Purpose: To study the effect of three nonionic surfactants on the protein-silicone oil interactions., Methods: The adsorption of Tween® 80, Pluronic® F68 and Tween® 20 at the silicone oil/water interface (using shifts in frequency (ΔF) and resistance (ΔR) with quartz crystal microbalance) was compared to the adsorption at air/water interface (using surface tension). Effect of surfactants on protein adsorption to the silicone oil/water interface was studied in sequential- and co-adsorption modes. Protein-surfactant binding in the bulk was measured using dynamic surface tension method., Results: Saturation of air/water and silicone oil/water interfaces by surfactants was observed at similar bulk concentrations. ΔF due to protein adsorption to the interface decreased only when surfactant was present as a pre-adsorbed species. Insignificant differences in the dynamic surface tension values of surfactant solutions were observed in the presence of protein., Conclusions: Similar hydrophobic forces were responsible for driving the surfactant adsorption at both air/water and silicone oil/water interfaces. Surfactants were effective in reducing the protein adsorption to the silicone oil only when introduced before or along with the protein. No significant binding between the protein and surfactants was observed in the bulk.

A practical, enantioselective synthesis of cis-2,5-disubstituted pyrrolidine is described. Application of an enzymatic DKR reduction of a keto ester, which is easily accessed through a novel intramolecular N→C benzoyl migration, yields syn-1,2-amino alcohol in >99% ee and >99:1 dr. Subsequent hydrogenation of cyclic imine affords the cis-pyrrolidine in high diastereoselectivity. By integrating biotechnology into organic synthesis and isolating only three intermediates over 11 steps, the core scaffold of β3-AR agonists is synthesized in 38% overall yield.

There is evidence in the literature that silicone oil, a lubricant, can induce aggregation in protein formulations delivered through prefilled syringes. Surfactants are commonly used to minimize protein-silicone oil and protein-container interactions; however, these interactions are not well characterized and understood. The purpose of this manuscript was to understand the competitive interactions of a fusion protein with the silicone oil in the presence of Tween(®) 20. An adsorption isotherm for Tween(®) 20 at the silicone oil/water interface, using silicone oil coated quartz crystals, was generated at 25°C to identify surface saturation concentrations. A concentration of Tween(®) 20 providing interfacial saturation was selected for protein adsorption studies at the silicone oil/water interface. The surfactant molecules adsorbed at the interface in a monolayer with a reduced viscoelastic character in comparison to the bound protein layer. A significant reduction in protein adsorption was observed when the surfactant was present at the interface. No desorption of the pre-adsorbed protein molecules was observed when Tween(®) 20 was introduced, suggesting that the protein has strong interactions with the interface. However, both, Tween(®) 20 and protein, adsorbed to the silicone oil/water interface when adsorption was carried out from a mixture of protein and Tween(®) 20., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In this study, we have used quartz crystal microbalance (QCM) to quantitate the adsorption of a protein on silicone oil coated surfaces as a function of protein concentration, pH and ionic strength using a 5 MHz quartz crystal. Protein adsorption isotherms were generated at different solution pH and ionic strengths. Surface saturation concentrations were selected from adsorption isotherms and used to generate adsorption profiles from pH 3.0 to 9.0, and at ionic strengths of 10 mM and 150 mM. At low ionic strength (10mM) and pH 5.0 (close to the isoelectric point of the protein), maximum adsorption of protein to the silicone oil surface was observed. At higher ionic strength (150 mM), no significant pH influence on adsorption was observed. QCM could be used as a reliable technique to study the binding of proteins to silicone oil coated surfaces., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A concise and efficient one-pot synthesis of functionalized sulfonylated pyridines via an S(N)Ar reaction of readily available pyridines and sodium sulfinate salts in the presence of tetrabutylammonium chloride is presented.

A mild, high-yielding procedure for the preparation of beta-ketophosphonates is described. The condensation is general with respect to the ester and phosphonate, and the products are obtained in high yields within minutes at 0 degrees C. The reaction procedure is operationally simple and amenable to large-scale preparations.

A one-pot, high-yielding iodination of hydroxypyridines and hydroxyquinolines is described. The iodination proceeds under mild conditions, and the products are obtained in high yield without the need for chromatographic purification. In addition, the iodination works on both 2- and 4-hydroxypyridines and -hydroxyquinolines.

This study investigated factors associated with vial filling with a positive displacement piston pump leading to formation of protein particles in a formulation of an IgG. We hypothesized that nanoparticles shed from the pump's solution-contact surfaces nucleated protein aggregation and particle formation. Vials of IgG formulation filled at a clinical manufacturing site contained a few visible particles and about 100,000 particles (1.5-3 microm) per mL. In laboratory studies with the same model (National Instruments FUS-10) of pump, pumping of 20 mg/mL IgG formulation resulted in about 300,000 particles (1.5-3 microm) per mL. Pumping of protein-free formulation resulted in 13,000 particles (1.5-15 microm) per mL. More than 99% of the particles were 0.25-0.95 microm in size. Mixing of protein-free pumped solution with an equal volume of 40 mg/mL IgG resulted in 300,000 particles (1.5-15 microm) per mL. Also, mixing IgG formulation with 30,000/mL stainless steel nanoparticles resulted in formation of 30,000 protein microparticles (1.5-15 microm) per mL. Infrared spectroscopy showed that secondary structure of IgG in microparticles formed by pumping or mixing with steel nanoparticles was minimally perturbed. Our results document that nanoparticles of foreign materials shed by pumps can serve as heterogeneous nuclei for formation of protein microparticles., ((c) 2008 Wiley-Liss, Inc. and the American Pharmacists Association)

Aggregation of partially folded intermediates populated during protein folding processes has been described for many proteins. Likewise, partially unfolded chains, generated by perturbation of numerous proteins by heat or chemical denaturants, have also been shown to aggregate readily. However, the process of protein aggregation from native-state conditions is less well understood. Granulocyte-colony stimulating factor (G-CSF), a member of the four-helix bundle class of cytokines, is a therapeutically relevant protein involved in stimulating the growth and maturation of phagocytotic white blood cells. Under native-like conditions (37 degrees C [pH 7.0]), G-CSF shows a significant propensity to aggregate. Our data suggest that under these conditions, native G-CSF exists in equilibrium with an altered conformation, which is highly aggregation prone. This species is enriched in 1-2 M GdmCl, as determined by tryptophan fluorescence and increased aggregation kinetics. In particular, specific changes in Trp58 fluorescence report a local rearrangement in the large loop region between helices A and B. However, circular dichroism, reactivity toward cyanylation, and ANS binding demonstrate that this conformational change is subtle, having no substantial disruption of secondary and tertiary structure, reactivity of the free sulfhydryl at Cys17 or exposure of buried hydrophobic regions. There is no indication that this altered conformation is important to biological activity, making it an attractive target for rational protein stabilization.

[reaction: see text] An intramolecular iminoacetonitrile [4 + 2] cycloaddition functions as the key step in an efficient total synthesis of the quinolizidine alkaloid (-)-217A.

We previously established that compression of monolayers containing the lipids in pulmonary surfactant, with or without the surfactant proteins, initially leads to phase separation. On further compression, however, phase coexistence terminates at a critical point that requires the presence of cholesterol. The studies reported here address the changes in the phospholipid phase diagram produced by cholesterol. We used the two systems of the lipids from calf surfactant with and without the surfactant proteins. For both systems, we began with the postulate that cholesterol had no effect on the composition of other constituents in the two phases, and then used the known behavior of interfacial tension at a critical point to test the two extreme cases in which the cholesterol partitions exclusively into condensed domains or into the surrounding film. Measurements of surface potential along with the fraction of the nonfluorescent area and the radius of the domains, both obtained by fluorescence microscopy, for films with and without cholesterol allowed calculation of the interfacial tension between the two phases. Only the model that assumes the presence of cholesterol within the domains accurately predicts a decreasing line tension during film compression toward the critical point. That model, however, also predicts an unlikely decrease during compression of the dipole moment density for the condensed phase. Our results are best explained in terms of cholesterol partitioning predominantly into the condensed domains, with a resulting partial redistribution of the phospholipids between the two phases., (Copyright 2002 Elsevier Science B.V.)