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Abstract: The convergent synthesis of the complete LL-Z1640-2 framework has been completed. This fast and efficient approach provides flexible access into the resorcyclic lactones. [Copyright &y& Elsevier]

The total synthesis of (+)-crocacin D has been achieved in 15 steps (9 isolated intermediates) and 14% overall yield from commercially available starting materials and using (+)-crocacin C as a key intermediate. A number of simplified analogues and their biological activities are also reported. [ABSTRACT FROM AUTHOR]

Biodegradation of estrogen hormone micropollutants is a well-established approach toward their remediation. Fluorescently labeled substrates are used extensively for rapid, near-real-time analysis of biological processes and are a potential tool for studying biodegradation processes faster and more efficiently than conventional approaches. However, it is important to understand how the fluorescently tagged surrogates compare with the natural substrate in terms of chemical analysis and the intended application. We derivatized three natural estrogens with BODIPY fluorophores by azide-alkyne cycloaddition click reaction and developed an analytical workflow based on simple liquid-liquid extraction and HPLC-PDA analysis. The developed methods allow for concurrent analysis of both fluorescent and natural estrogens with comparable recovery, accuracy, and precision. We then evaluated the use of BODIPY-labeled estrogens as surrogate substrates for studying biodegradation using a model bacterium for estrogen metabolism. The developed analytical methods were successfully employed to compare the biological transformation of 17β-estradiol (E2), with and without the BODIPY fluorescent tag. Through measuring the complete degradation of E2 and the transformation of BODIPY-estradiol to BODIPY-estrone in the presence of a co-substrate, we found that BODIPY-labeled estrogens are biologically viable surrogates for investigating biodegradation in environmental bacteria., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: Anogenital warts are a common human papillomavirus infection. They cause emotional distress, especially when they are in the anogenital region. Cryotherapy is a first-line treatment. Previous clinical trials and case series have reported variable results with retinoids (isotretinoin) as adjuvant therapy., Objective: To determine the safety and efficacy of low-dose oral isotretinoin as adjuvant treatment of anogenital warts., Methods: Forty-six patients with anogenital warts were randomly assigned to isotretinoin + cryotherapy (n = 23) or only cryotherapy (n = 23). Patients were allocated via an interactive web-based randomization system. Evaluators were blinded to treatments. Isotretinoin 20 mg/daily + cryotherapy or cryotherapy were prescribed for 6 weeks. Patients were followed for 4 months. Genotyping of lesions was performed before treatment started. Dermatology Life Quality Index (DLQI) and Columbia-Suicide Severity Rating Scale (C-SSRS) were measured at the beginning and end of therapy. All patients completed the study., Results: Both Groups had 50% clearance at the end of treatment. Recurrence in the combined group was not significantly lower than in the cryotherapy group (P = 0.59). Improvement was observed in the DLQI of all patients in both groups (P = 0.001). No suicidal intention was detected with the C-SSRS. Two patients (one in each group) had liver function test abnormalities after treatment., Conclusion: Combined therapy showed a slight not significant efficacy for anogenital warts in Hispanic patients. Low-dose isotretinoin seems to be safe even when it is used with cryotherapy on anogenital warts., Trial Registration: On April 25, 2019 with registration number DE19-00004, CONBIOÉTICA-19-CEI-001-20160404. Prospectively registered., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Current treatment modalities for disseminated cutaneous malignant melanoma (CMM) improve survival; however, relapses are common. A number of receptor tyrosine kinases (RTKs) including EGFR and MET have been reported to be involved in CMM metastasis and in the development of resistance to therapy, targeting the mitogen-activated protein kinase (MAPK pathway). IHC analysis showed that patients with higher MET protein expression had a significantly shorter overall survival. In addition, silencing of MET caused an upregulation of EGFR and p-AKT, which was abrogated by concomitant silencing of MET and EGFR in CMM cells resistant to MAPK-targeting drugs. We therefore explored novel treatment strategies using clinically approved drugs afatinib (ERBB family inhibitor) and crizotinib (MET inhibitor), to simultaneously block MET and ERBB family RTKs. The effects of the combination were assessed in cell culture and spheroid models using established CMM and patient-derived short-term cell lines, and an in vivo xenograft mouse model. The combination had a synergistic effect, promoting cell death, concomitant with a potent downregulation of migratory and invasive capacity independent of their BRAF/NRAS mutational status. Furthermore, the combination attenuated tumor growth rate, as ascertained by the significant reduction of Ki67 expression and induced DNA damage in vivo. Importantly, this combination therapy had minimal therapy-related toxicity in mice. Lastly, the cell cycle G2 checkpoint kinase WEE1 and the RTK IGF1R, non-canonical targets, were altered upon exposure to the combination. Knockdown of WEE1 abrogated the combination-mediated effects on cell migration and proliferation in BRAF mutant BRAF inhibitor-sensitive cells, whereas WEE1 silencing alone inhibited cell migration in NRAS mutant cells. In summary, our results show that afatinib and crizotinib in combination is a promising alternative targeted therapy option for CMM patients, irrespective of BRAF/NRAS mutational status, as well as for cases where resistance has developed towards BRAF inhibitors.

[reaction: see text] A fast, flexible, and efficient approach for the stereocontrolled synthesis of enamides has been developed starting from lactams and amides through the use of imides. This new approach provides access to enamide systems not easily or currently accessible through other approaches.

The first enantioselective synthesis of C(3) fluoro-MEP is herein reported. The synthetic pathway developed takes advantage of a selective hydrofluorination of a 2,3-epoxy-1-alcohol to introduce the required tertiary fluoride unit.

[structure: see text] A highly stereocontrolled total synthesis of the cytotoxic macrolide (-)-callipeltoside A has been achieved in 23 steps (4.8% overall). Notable features include a novel asymmetric vinylogous aldol reaction to install the C13 stereocenter and (E)-trisubstituted alkene, an anti-selective aldol addition, a Sonogashira coupling, and, last, a Schmidt-type glycosylation to attach the sugar unit.