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We report the unprecedented diastereoselective synthesis of novel [6,6,6]-trioxa-fused ketals via AgOTf-catalyzed cascade annulation of 5-hexyn-1-ols (with primary or secondary hydroxyl groups) and aldehydes through a [2+2+1+1] pathway. In contrast, 5-hexyn-1-ols with tertiary hydroxyl groups yield hexahydro-2 H -chromenes via a [3+1+1+1] pathway.

Objective: Signed in 2019, New York State's Reproductive Health Act enabled expansion of abortion care up to 28 weeks for any indication. This study aimed to describe how implementation of the New York State Reproductive Health Act affected abortion provision among the state's regional perinatal centers (RPCs)-tertiary referral centers for complex pregnancies that may care for patients seeking abortion later in pregnancy. A secondary objective was to identify barriers to and facilitators of expanding abortion care., Methods: From January to May 2023, we recruited clinicians from the 17 New York RPCs, including family planning specialists, maternal-fetal medicine specialists, and genetic counselors. Respondents completed an online survey. We then invited respondents to complete an in-depth interview. We calculated descriptive statistics to characterize the study population and summarize survey responses. We analyzed qualitative interview data using thematic analysis., Results: Twenty-nine respondents completed the survey, representing 16 of 17 New York State RPCs. Seventeen respondents, representing 11 RPCs, completed an interview. All institutions provided abortion care. Twenty-three of 29 survey respondents (79%) reported barriers to providing abortion for any indication after 24 weeks from last menstrual period (LMP). Eighteen of 29 (62%) reported barriers to providing abortion after 24 weeks LMP for maternal or fetal indications. The most commonly reported barriers in the survey results were staff resistance and institutional policy. During interviews, respondents identified staff discomfort, restrictive institutional policies, and lack of clarity around policy as barriers, while highlighting advocates and collaboration within their institutions as facilitators to expansion of abortion services later in pregnancy., Conclusions: RPCs in New York State face barriers in providing abortion, especially after 24 weeks LMP, even though they are ideally situated to provide such care. These barriers exist despite the legality of abortion after 24 weeks in New York and policy efforts to expand access to abortion., (Copyright © 2024 Jacobs Institute of Women's Health, George Washington University. Published by Elsevier Inc. All rights reserved.)

Additive free aminolysis method developed for the depolymerization/upcycling of polycarbonates. We report here chemical recycling of polycarbonate under ambient conditions to get its monomer bisphenol A, monoaminocarbamate and biscarbamates in 1 : 2 : 1 ratio respectively. By employing the secondary amine as the aminating reagent, facilitates the depolymerization to work under additive/catalyst free conditions. The developed method deals with depolymerization of waste polycarbonates and works even with late-stage amine derivatives such as amoxapine and desloratadine which are drugs molecules known to treat neurotic disorders and allergies respectively. The reaction can be scaled up and works with similar efficacy which depicts the efficiency of the depolymerization of wasteend-of-life polycarbonate plastic waste. The biscarbamate and bisphenol-A was further subjected for the post functionalization to obtain amides and phenol in good yields., (© 2024 Wiley-VCH GmbH.)

A direct electrosynthesis/photocatalyst-free, atom-economical, and efficient method for the selective synthesis of ( E )-3-amino-2-thiocyanato-α,β-unsaturated carbonyl compounds is described through a given protocol. The present approach features the use of inexpensive ammonium thiocyanate to achieve dual functionalization of 1,3-dicarbonyl compounds using TBHP as an oxidant, providing a rapid and practical route to the selective formation of both C-N and C-S bonds via a radical process. This method offers a broad substrate scope with excellent yield and allows for further exploration of the products to construct heterocyclic compounds and other functionalities.

The synthesis and characterization of a bis-iron(II) complex was accomplished upon treatment of a phosphine free NNN-pincer ligand (L) with FeCl 2 ·4H 2 O under ambient conditions. The deep greenish colored iron(II) complex (Fe-1) was characterized by a single-crystal X-ray diffraction study along with IR spectroscopy, UV-Vis spectroscopy, mass spectrometry, and elemental analysis. The Fe-1 complex was tested for the transfer semi-hydrogenation of terminal alkynes to the corresponding alkenes through the dehydrogenation of dimethyl amine-borane. This procedure enables the conversion of various structurally different terminal alkynes to alkenes under mild conditions. Control experiments were performed to shed light on the possible intermediates generated during the present protocol.

Bismuth(III) triflate-catalyzed [4+2]-annulation of cyclic N -sulfonyl ketimines (derived from saccharin) and alkynyl alcohols (4-pentyn-1-ols and 5-hexyn-1-ols) has been reported. This cascade annulation provides a diverse array of polycyclic spiro-and-fused N , O -ketals with excellent substrate scope, good isolated yields, and diastereoselectivities under mild reaction conditions.

Herein, we developed a series of compounds featuring spiro[3-arylcyclohexanone]oxindoles through Barbas [4 + 2] cycloaddition reactions between isatylidene malononitrile and α,β-unsaturated ketones using l-proline as an organocatalyst. The reported methodology offers many advantages such as mild reaction conditions, diverse substrate scope with high yields, easy reaction setup, and use of easily synthesizable starting materials., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

In this paper, we report "carbamate protected" 2-aminopyrimidinedione-based Janus G-C nucleobases (2-APD Janus G-C nucleobases) featuring polymerizable groups and self-complementary triple H-bonding motifs DDA and AAD as building blocks for developing smart polymers and self-healing materials. The carbamate-masked H-bonding motif, cleavable under acidic (BOC group) or photocleavable ( O -nitrobenzyl group) conditions, would facilitate the synthesis of smart polymers by alleviating aggregation during polymerization which in turn would exclude self-assembly-assisted solubility issues. Ready accessibility in excellent yields coupled with the possibility for facile introduction of polymerizable groups would make these building blocks excellent candidates for diverse polymerization applications.

The planar morphology of the backbone significantly contributes to the subtle optoelectronic features of π-conjugated polymers. On the other hand, the atomistic tuning of an otherwise identical π-backbone could also impact optoelectronic properties systematically. In this manuscript, we compare a series of 3,4-cycloalkylchalcogenophenes by tuning them atomistically using group-16 elements. Additionally, the effect of systematically extending these building blocks in the form of oligomers and polymers is studied. The size of the 3,4-substitution affected the morphology of the oligomers. In addition, the heteroatoms contributed to a further alteration in their geometry and resultant optoelectronic properties. The chalcogenophenes, containing smaller 3,4-cycloalkanes, resulted in lower bandgap oligomers or polymers compared to those with larger 3,4-cycloalkanes. Natural bonding orbital (NBO) calculations were performed to understand the disparity alongside the contour maps of frontier molecular orbitals (FMO).

Herein, we report the first total synthesis of α-glycosidase inhibitor (3 R , 4 S )-6-acetyl-3-hydroxy-2,2-dimethylchroman-4-yl ( Z )-2-methylbut-2-enoate as well as its enantiomer. Our synthesis confirms the chromane structure separately proposed by Navarro-Vazquez and Mata, on the basis of DFT computations. Furthermore, our synthesis allowed us to determine the absolute configuration of the natural compound as (3 S , 4 R ) and not (3 R , 4 S ).

Benzoheteroles and vinyl sulfones are the most promising pharmaceutical relevance motifs, yet the hybrid analogues of these scaffolds still need to be explored. We report herein a general and highly efficient Pd(OAc) 2 -catalyzed intramolecular cyclization and vinylation of o -alkynylphenols/ o -alkynylanilines with ( E )-β-iodovinyl sulfones under mild reaction conditions. A direct C(sp 2 )-C(sp 2 ) cross-coupling is enabled for the diversity-oriented synthesis of vinyl sulfone-tethered benzofurans and indoles in good to high yields with excellent stereoselectivity. Notably, this tandem process was consistent at the gram scale, and in situ, generation of 2-(phenylethynyl)phenol has also been utilized in a scalable synthesis. Late-stage synthetic transformations were also further explored, including isomerization and desulfonylative-sulfenylation. Moreover, several control experiments were accomplished, and we proposed a plausible mechanism based on existing experimental results.

Benzoheteroles are valuable scaffolds in medicinal chemistry, but the direct synthesis of 3-vinyl benzoheterole analogues remains unexplored. A rationally designed new class of 1,6-enyne-containing propargylic alcohols has been prepared for the modular synthesis of 3-alkenyl benzoheteroles. Ag-catalyzed cascade radical sulfonylative-cycloannulation of 1,6-enynols with sodium sulfinates is realized to access a wide variety of 2,3-disubstituted benzoheteroles in good to high yields. Moreover, a three-component coupling of 1,6-enynols, aryldiazonium salts, and Na 2 S 2 O 5 (as an SO 2 surrogate) has been achieved to deliver benzoheterole derivatives in moderate to good yields. Of note, a scalable reaction and late-stage synthetic transformations were successfully demonstrated. A plausible mechanism is also presented based on the existing experimental results and control experiments.

The nature of solvent is a key factor for stereoselective mono- and bis-thiolation of ( E )-β-iodovinyl sulfones with thiols under basic conditions. A novel and unprecedented vicinal bisthiolation of ( E )-β-iodovinyl sulfones with thiols under the influence of K 2 CO 3 /DMSO at room temperature for quick assembly of ( E )-1,2-dithio-1-alkenes is presented. Solvent-induced stereoselective monosulfenylation of ( E )-β-iodovinyl sulfones with thiols has also been established for the synthesis of both ( E )- and ( Z )-1,2-thiosulfonylethenes in MeCN and MeOH, respectively. Moreover, K 2 CO 3 -mediated desulfonylative-sulfenylation of ( Z )-1,2-thiosulfonylethenes with thiols in DMSO furnished unsymmetrical ( Z )-1,2-dithio-1-alkenes for the first time. The solvent-dependent versatile reactivity of ( E )-β-iodovinyl sulfones has been successfully explored to provide a set of ( E )-/( Z )-1,2-dithio-1-alkenes and ( E )-/( Z )-1,2-thiosulfonyl-1-alkenes in good to high yields with excellent stereoselectivities. Notably, this operationally simple process utilizes a broad substrate scope with good functional group tolerance and compatibility. The efficacy of the process has been proven for gram-scale reactions, and plausible mechanistic models are outlined on the basis of experimental results and control experiments.

Crystallization experiments performed with highly supercooled solutions produced highly pure (>99 wt %) and highly crystalline mesocrystals of curcumin from impure solutions (∼22% of two structurally similar impurities) in one step. These mesocrystals exhibited a crystallographic hierarchy and were composed of perfectly or imperfectly aligned nanometer-thick crystallites. X-ray diffraction and spectroscopic analysis confirmed that the spherulites are a new solid form of curcumin. A theoretical hypothesis based on particle aggregation, double nucleation, and repeated secondary nucleation is proposed to explain the spherulite formation mechanism. The experimental results provide, for the first time, evidence for an organic molecule to naturally form spherulites without the presence of any stabilizing agents. Control experiments performed with highly supercooled pure solutions produced spherulites, confirming that the formation of spherulites is attributed to the high degree of supercooling and not due to the presence of impurities. Likewise, control experiments performed with a lower degree of supercooling produced impure crystals of curcumin via classical molecular addition mechanisms. Collectively, these experimental observations provide, for the first time, evidence for particle-mediated crystallization as an alternate and efficient method to purify organic compounds., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Purpose of Review: Hormonal contraception provides women living with HIV the ability to control their fertility and avoid pregnancy-related morbidity. Due to shared metabolic pathways, there has been concern over drug-drug interactions between hormonal contraception and anti-retroviral therapy, which may affect the drugs' safety and efficacy. This article aims to provide an updated review of the most recent data around hormonal contraceptives and anti-retroviral therapy., Recent Findings: Prior data have suggested possible pharmacologic interactions between certain hormonal contraceptives and anti-retroviral therapy. The most significant interactions implicated include those between progestin-based contraceptive implants and efavirenz as well as between combined hormonal contraceptives and protease inhibitors. Most past studies, however, feature small sample sizes with few clinical outcomes reported., Summary: Recent data since 2017 have largely affirmed prior studies on this topic, showing possible pharmacokinetic relationships between certain contraceptives and anti-retrovirals. Notably, while the effectiveness of progestin-based contraceptives, specifically the implant, appears reduced with efavirenz use, the overall effectiveness may remain higher than most other contraceptive methods. Larger studies are needed to provide further guidance before contraceptive-prescribing recommendations can be changed., Competing Interests: Conflicts of Interest/Competing Interests: Dr. Haddad has nothing to disclose. Dr. Krishna has nothing to disclose.

The solubility of butamben has been measured gravimetrically in pure methanol, 1-propanol, 2-propanol, 1-butanol, and toluene over the temperature range 268-298 K. Polymorph transition and melting temperatures, associated enthalpy changes, and the heat capacity of the solid forms and the supercooled melt have been measured by differential scanning calorimetry. Based on extrapolated calorimetric data, the Gibbs energy, enthalpy and entropy of fusion, and the activity of solid butamben (the ideal solubility) have been calculated from below ambient temperature up to the melting point. Activity coefficients of butamben at equilibrium in the different solvents have been estimated from solubility data and the activity of the solid, revealing that all investigated systems exhibit positive deviation from Raoult's law. Solubility data are well correlated by a semiempirical regression model. On a mass basis, the solubility is clearly higher in methanol than in the other solvents, but mole fraction solubilities are very similar across all 5 solvents. The 2 known polymorphs are enantiotropically related, and the transition point is located at 283 K. Polymorph interconversions occur within 0.3 K of the transition point even in the solid state, and the 2 forms exhibit strong similarities in investigated properties., (Copyright © 2019 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Controlling mechanical properties of ordered organic materials remains a formidable challenge, despite their great potential for high performance mechanical actuators, transistors, solar cells, photonics, and bioelectronics. Here we demonstrate a crystal engineering approach to design mechanically reconfigurable, plastically flexible single crystals (of about 10) of three unrelated types of compounds by introducing active slip planes in structures via different noninterfering supramolecular weak interactions, namely van der Waals (vdW), π-stacking, and hydrogen bonding groups. Spherical hydrophobic groups, which assemble via shape complementarity (shape synthons), reliably form low energy slip planes, thus facilitating an impressive mechanical flexibility, which allowed molding the crystals into alphabetical characters to spell out "o r g a n i c c r y s t a l". The study, which reports the preparation of a series of exotic plastic crystals by design for the first time, demonstrates the potential of soft interactions for tuning the mechanical behavior of ordered molecular materials, including those from π-conjugated systems.

The structure and mechanical properties of crystalline materials of three boron difluoride dibenzoylmethane (BF2dbm) derivatives were investigated to examine the correlation, if any, among mechanochromic luminescence (ML) behaviour, solid-state structure, and the mechanical behaviour of single crystals. Qualitative mechanical deformation tests show that the crystals of BF2dbm( (t) Bu)2 can be bent permanently, whereas those of BF2dbm(OMe)2 exhibit an inhomogeneous shearing mode of deformation, and finally BF2dbmOMe crystals are brittle. Quantitative mechanical analysis by nano-indentation on the major facets of the crystals shows that BF2dbm( (t) Bu)2 is soft and compliant with low values of elastic modulus, E, and hardness, H, confirming its superior suceptibility for plastic deformation, which is attributed to the presence of a multitude of slip systems in the crystal structure. In contrast, both BF2dbm(OMe)2 and BF2dbmOMe are considerably stiffer and harder with comparable E and H, which are rationalized through analysis of the structural attributes such as the intermolecular interactions, slip systems and their relative orientation with respect to the indentation direction. As expected from the qualitative mechanical behaviour, prominent ML was observed in BF2dbm( (t) Bu)2, whereas BF2dbm(OMe)2 exhibits only a moderate ML and BF2dbmOMe shows no detectable ML, all examined under identical conditions. These results confirm that the extent of ML in crystalline organic solid-state fluorophore materials can be correlated positively with the extent of plasticity (low recovery). In turn, they offer opportunities to design new and improved efficient ML materials using crystal engineering principles.

Psoriasis is a T-helper-1 (Th1)/Th17-mediated chronic inflammatory skin disease, characterised by hyperproliferation of keratinocytes. Psoriasis and cardiovascular disease share similar pathogenic mechanisms such as vascular endothelial cell dysfunction, oxidative stress and metabolic syndrome. 25-hydroxy vitamin D is an immune-regulatory hormone, with the ability to reduce cellular proliferation in psoriasis. Ischaemia-modified albumin (IMA) is a marker of oxidative stress. This study examined 25-hydroxy vitamin D, IMA and high-sensitivity C-reactive protein (hs-CRP) levels in patients with psoriasis, in comparison with healthy controls and their possible association with disease severity. A total of 43 cases of psoriasis and 43 controls were included in this cross-sectional study, and severity grading was performed according to psoriasis area severity index (PASI) scoring. Serum 25-hydroxy vitamin D, IMA and hs-CRP were evaluated in all study subjects. In psoriasis, 25-hydroxy vitamin D showed a significant decline, while hs-CRP and IMA levels were significantly elevated, as compared with controls. Serum 25-hydroxy vitamin D showed a significant negative correlation with PASI score. hs-CRP and IMA showed a significant positive correlation with PASI score. Significant negative correlation was observed between 25-hydroxy vitamin D and hs-CRP; 25-hydroxy vitamin D and IMA levels in psoriasis. The results indicate that psoriasis is associated with significantly lowered 25-hydroxy vitamin D levels, along with increased systemic inflammation and oxidative stress, especially in severe disease. Thus, vitamin D supplementation might reduce systemic inflammation and oxidative stress and help in delaying the pathogenesis of co-morbidities associated with psoriasis.

Unprecedented synthesis of functionalized indoles of potential pharmacological interest has been developed via a Pd-mediated cascade reaction involving an intramolecular Heck coupling followed by the construction of a fused cyclopentane ring in a single pot.

A new, versatile and direct Pd-mediated method involving intramolecular cyclization of N-(2-iodoaryl)-N-(1-alkyl-1H-indol-2-yl)alkane/arene/heteroarene sulfonamide has been developed leading to a diverse and unique class of indolo[2,3-b]indoles for the potential inhibition of sirtuins.

Thiasalen podand 9 having S2N2 donor set has been synthesized by the condensation of 2-methylthiobenzaldehyde with ethylenediamine. The reaction of the thiasalen podand ligand with Pd(II) afforded two complexes depending on the reaction time. Shorter reaction time (5 min) afforded thioether complex 10; whereas with increase in reaction time (4 h) thioether-thiolate complex 11 was obtained via cleavage of one of the two S-C(Me) bonds of bis(methyl)thiasalen podand upon complexation. The reaction of 9 with Pt(II) afforded only thiolate-thioether complex 12 independent of the reaction time. The cleavage of both the S-C(Me) bonds of bis(methyl)thiasalen to afford bisthiolate complexes has never been observed. The structures of thiasalen podands and all three complexes have been determined by single crystal X-ray diffraction analysis. All three complexes possess a square planar geometry around the metal centres. Weak van der Waals interactions through C-H···F interactions are present in all three complexes leading to the formation of supramolecular synthons and the supramolecular structures are stabilized by aromatic π···π interactions, which leads to the formation of 3D pseudo-double helical network packing. Under similar conditions bis(methyl)salen did not form any complexes with Pd(II) and Pt(II).

A rapid, versatile and one-pot Cu-mediated domino reaction has been developed for facile assembly of two six membered fused N-heterocyclic rings leading to novel small molecules as potential inhibitors of PDE4.

A conceptually new and straightforward introduction of sulfonyl groups at the C-7 position of an indole ring has been achieved via AlCl(3) mediated unexpected regioselective sulfonyl group migration for N-alkyl/aryl/heteroarylsulfonyl indoles affording potential inhibitors of Mycobacterium tuberculosis H37Rv chorismate mutase.

Novel thieno[2,3-d]pyrimidines containing a cyclohexane ring fused with a six- or five-membered heterocyclic moiety along with a benzylic nitrile were designed as potential inhibitors of PDE4. Expeditious synthesis of these compounds was carried out via a multi-step sequence consisting of a few key steps such as Gewald reaction, Dieckmann type cyclisation and Krapcho decarboxylation. This newly developed strategy involved construction of the thienopyrimidine ring followed by the cyclohexanone moiety and subsequently the fused heterocyclic ring. A number of thieno[2,3-d]pyrimidine based derivatives were synthesized using this method some of which showed promising PDE4B inhibitory properties. One of them was tested for PDE4D inhibition in vitro and dose dependent inhibition of TNF-α. A few selected molecules were docked into the PE4B protein the results of which showed good overall correlations to their observed PDE4B inhibitory properties in vitro. The crystal structure analysis of representative compounds along with hydrogen bonding patterns and molecular arrangement present within the molecule is described.

Regioselective construction of a fused 2-ylidene chromene ring was achieved for the first time by using AlCl(3)-induced C-C bond formation followed by Pd/C-Cu mediate coupling-cyclization strategy. A number of chromeno[4,3-b]quinoxaline derivatives were prepared by using this strategy. Single crystal X-ray diffraction study of a representative compound e.g. 6-(2,2-dimethylpropylidene)-4-methyl-6H-chromeno[4,3-b]quinoxalin-3-ol confirmed the presence of an exocyclic C-C double bond with Z-geometry. The crystal structure analysis and hydrogen bonding patterns of the same compound along with its structure elaboration via propargylation followed by Sonogashira coupling of the resulting terminal alkyne is presented. A probable mechanism for the formation of 2-ylidene chromene ring is discussed. Some of the compounds synthesized showed anticancer properties when tested in vitro.

A regioselective route to novel mono triazolyl substituted quinolines has been developed via copper-catalyzed azide-alkyne cycloaddition (CuAAC) of 2,4-diazidoquinoline with terminal alkynes in DMF. The reaction provided bis triazolyl substituted quinolines when performed in water in the presence of Et(3)N. A number of the compounds synthesized showed promising anti-proliferative properties when tested in vitro especially against breast cancer cells., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Improving salinity and drought tolerance of crop plants has been an important aim of modern agricultural development, which depends on understanding the functions of genes expressed during the process of stress adaptation. EST resources are an efficient and cost-effective solution to gene discovery. Jatropha curcas is emerging as the most promising tree oil seed as a source of biodiesel. To identify genes that respond to abiotic stress, in the present study, we report 1240 ESTs generated from root cDNA libraries of J. curcas. ESTs were clustered and assembled into a collection of 865 unigenes, with 107 contigs and 758 singleton sequences. The putative functions of several ESTs could be assigned by similarity to plant gene sequence comparisons. It was found that 23 full-length CDS (34%) and the majority of transcription factors had sequence similarity to genes known to be involved in abiotic and biotic stress tolerance. The expression pattern of nine selected genes revealed that these genes are differentially expressed in various tissues during adaptation to stress. The data could serve as a critical resource to enable plant improvement programmes towards enhancing the adaptability of J. curcas to growth on marginal lands., (© 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.)

A number of novel 1,8-disubstituted 5,5-dimethyl-4,5-dihydro-1H-benzo[g]indazoles based on a conformationally restricted pyrazole framework have been designed as potential inhibitors of PDE4. All these compounds were readily prepared by using simple chemistry strategy. The in vitro PDE4B inhibitory properties and molecular modeling studies of some of the compounds synthesized along with the X-ray single crystal data of a representative compound is presented., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Molecular iodine facilitated the reaction of 5,5-dimethyl-1,3-cyclohexanedione with aromatic aldehydes in iso-propanol affording a variety of 1,8-dioxo-octahydroxanthenes in high yields. Most of the compounds synthesized showed good anti-proliferative properties in vitro against three cancer cell lines and 9-(2-hydroxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione possessing a 2-hydroxy phenyl group at C-9 position was found to be promising. Further structure elaboration of the same compound and the crystal structure analysis and hydrogen bonding patterns of another compound that is, 9-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione prepared by using this methodology is presented., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A direct and single-step method has been developed for the synthesis of mono and 2,3-disubstituted quinoxalines by using a AlCl(3) induced (hetero)arylation of 2,3-dichloroquinoxaline. Both symmetrical and unsymmetrical 2,3-disubstituted quinoxalines can be prepared conveniently by using this method under appropriate reaction conditions. The reaction proceeds via C-C bond formation and can be utilized for the preparation of a variety of quinoxaline derivatives from readily available starting materials and reagents. The molecular structure of a representative compound was confirmed by single crystal X-ray diffraction study. Some of the compounds synthesized were tested for chorismate mutase inhibitory properties in vitro and one compound showed promising activity representing one of the few examples of chorismate mutase inhibition by a heteroarene based small molecule., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Selenophene and thiophene capped cyclopenta[c]selenophenes were synthesized and characterized. Crystal structure determination of some representative compounds revealed that the substitution at 3,4-position in the form of cyclopentane ring of selenophene or thiophene does not make any significant twist in the trimer backbone, making the cooligomer nearly planar. All the cooligomers were electrochemically polymerized and compared with thiophene capped cyclopenta[c]thiophene polymer. DFT calculations predict that the cyclopentane substitution on the third repeating unit (and in general) of one dimensional polymer neither disturb the planarity nor causes any significant twist on the polymeric backbone unlike the 3,4-dialkyl substitution. The electrochemically prepared selenophene based polymers showed low band gap compared to that of thiophene analogues. Cyclopentane substitution on selenophene as well as thiophene makes the resulting polymer oxidatively more stable when compared to more familiar poly-ethylenedioxythiophene (PEDOT) or poly-ethylenedioxyselenophene (PEDOS) systems. Alternate polymers of cyclopenta[c]selenophenes (CPS)/cyclopenta[c]thiophene (CPT) and thiophene/selenophene possess the energy of HOMO and LUMO significantly lower than that of homopolymers of CPS and CPT, however, possess higher band gap than PCPS.

A one-pot Yb(III)-mediated cascade reaction has been developed leading to small molecules based on a novel structural motif, i.e. quinazolin-4-one moiety fused with an isoquinoline ring, for potential inhibition of TNF-α., (This journal is © The Royal Society of Chemistry 2011)

A sequential Pd-mediated multi-component reaction followed by Suzuki or Heck or Sonogashira coupling in a single pot has been developed for the synthesis of functionalized pyrroles as potential inhibitors of PDE4.

New bis (alkyl) selenosalen podand ligands having Se2N2 donor sites have been synthesized by the condensation of unsymmetrical o-formylphenyl alkyl selenide (1-3) with ethylenediamine. The reaction of bis(alkyl)selenosalen podands with Pd(II) and Pt(II) afforded selenoether-selenolate coordination complexes 7-10via cleavage of one of the two Se-C(alkyl) bonds of bis(alkyl)selenosalen podands upon complexation. DFT calculations revealed that the cleavage of Se-C(alkyl) bonds occurred possibly via S(N)2 mechanism instead of a sequence of oxidative addition and reductive elimination reactions. The spectral data and elemental analyses confirmed the formation of selenoether-selenolate complexes. The structures of the podands N,N'-bis[(2-methylseleno)phenylmethylene]-1,2-ethanediamine (4), N,N'-bis[(2-decylseleno)phenylmethylene]-1,2-ethanediamine (5) and the selenoether-selenolate complex 8 have been determined by single crystal X-ray diffraction analysis. The crystal structure of 5 showed SeH interaction with a ladder like 3D supramolecular arrangement via interdigitation of long alkyl chains. Comparison of crystal packing of podands 4 and 5 indicates that the alkyl chain length has significant impact on the crystal packing. The platinum selenolate complex 8 shows a square planar arrangement around the Pt centre, where the Se atoms in the selenolate and the selenoether have nearly equal Pt-Se bond length., (This journal is © The Royal Society of Chemistry 2011)

A method for isolating transcriptionally active RNA for downstream applications from diverse tissues of Jatropha curcas, a plant rich in latex, lipids, waxes, polysaccharide, polyphenols, and secondary metabolites, is described. The described method uses alkaline borate buffer during tissue homogenization to negate the formation of viscous gel observed in guanidium-salt-containing methods. By this method, quality RNA was extracted from leaf, immature inflorescence, endosperm, and root tissues with yields ranging from 1.80 to 7.80mg/100mg fresh weight (FW). The total RNA obtained was found to be suitable for poly(A)(+)RNA purification, complementary DNA (cDNA) synthesis, cloning of full-length cDNA, and cDNA library construction., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Concurrent construction of five and six membered fused N-heretocyclic ring was achieved via a conceptually new three-component reaction affording 6,6a-dihydroisoindolo[2,1-a]quinazoline-5,11-diones as novel inhibitors of TNF-αin vitro. This represents one of the few examples of direct TNF-α inhibition by small molecules., (© The Royal Society of Chemistry 2011)

Background: Breast cancer is one of the most prevalent cancers in the world and more than one million women are diagnosed leading to 410,000 deaths every year. In our previous studies new chalcone-imidazolone conjugates were prepared and evaluated for their anticancer activity in a panel of 53 human tumor cell lines and the lead compounds identified were 6 and 8. This prompted us to investigate the mechanism of apoptotic event., Results: Involvement of pro-apoptotic protein (Bax), active caspase-9 and cleavage of retinoblastoma protein was studied. Interestingly, the compounds caused upregulation of p21, check point proteins (Chk1, Chk2) and as well as their phosphorylated forms which are known to regulate the DNA damage pathway. Increased p53BP1 foci by immunolocalisation studies and TRF1 suggested the possible involvement of telomere and associated proteins in the apoptotic event. The telomeric protein such as TRF2 which is an important target for anticancer therapy against human breast cancer was extensively studied along with proteins involved in proper functioning of telomeres., Conclusions: The apoptotic proteins such as Bax, active caspase-9 and cleaved RB are up-regulated in the compound treated cells revealing the apoptotic nature of the compounds. Down regulation of TRF2 and upregulation of the TRF1 as well as telomerase assay indicated the decrease in telomeric length revealing telomeric dysfunction and thereby controlling the rapid rate of cell proliferation. In summary, chalcone-imidazolone conjugates displayed significant DNA damage activity particularly at telomeres and caused both apoptosis and senescence-like growth arrest which suggested that these compounds have potential activity against breast carcinoma.