Useful approach to the synthesis of aryl thio- and selenoglycosides in the presence of rongalite

A simple, mild, and cost effective methodology has been developed for the synthesis of aryl thio-and selenoglycosides from glycosyl halides and diaryl dichalcogenides. Diaryl dichalcogenides undergo reductive cleavage in the presence of rongalite (HOCH2SO2Na) to generate a chalcogenide anion in situ followed by reaction with glycosyl halides to furnish the corresponding aryl thio- and selenoglycosides in excellent yields. Using this protocol, synthesis of 4-methyl-7-thioumbelliferyl-beta-D-cellobioside (MUS-CB), a fluorescent non-hydrolyzable substrate analogue for cellulases has been achieved. (C) 2014 Elsevier Ltd. All rights reserved

Synthesis of mixed glycosyl disulfides/selenenylsulfides using benzyltriethylammonium tetrathiomolybdate as a sulfur transfer reagent

An easy and mild method has been developed for the synthesis of mixed glycosyl disulfides/selenenylsulfides from glycosyl halides and diaryl/dialkyl dichalcogenides in the presence of benzyltriethylammonium tetrathiomolybdate (BnEt3N)(2)MoS4]. The salient feature of this method is the sulfur transfer from BnEt3N](2)MoS4 to form glycosyl disulfides which with excess tetrathiomolybdate further undergo exchange reaction with other dichalcogenides in a one-pot operation. (C) 2014 Elsevier Ltd. All rights reserved

Depression and Stress among Tribal Migrant Rural Women of India

Background: India's tribal women are the primary breadwinners, yet they are socially and economically disadvantaged, with high rates of poverty, illiteracy, unemployment, and social insecurity, all of which contribute to a high percentage of mental illness among these women. Aim: The purpose of this study was to look into the levels of depression and stress experienced by rural tribal migrant women in India. Materials and Methods: Stratified random sampling was used to collect data on two subgroups of age (younger and older) and ethnicity (tribal and non-tribal). A total of 1000 rural migrant labour women were picked from various blocks and villages throughout the districts. Aaron T. Beck's Beck Depression Inventory (BDI-II) was used to assess depression, whereas Shamsunder et al. (1986) and Goutam et al. (1987) introduced General Health Questionnaire (GHQ) -12 was used to assess stress. Results: The older labour sample group had a higher level of sadness and stress than the younger migrant group, according to the findings. In comparison to the non-tribal sample group, the tribal sample showed a higher level of sadness and stress. Conclusion: It was concluded from the study that level of depression and stress was found higher among tribal women sample as compared to non-tribal sample and level of depression and stress was found higher among older women sample as compared to younger sample

EFFICIENT SYNTHESIS OF O-LINKED GLYCOCONJUGATES OF AMINO ACIDS FROM CARBOHYDRATE-DERIVED DONOR-ACCEPTOR CYCLOPROPANES

N-Iodosuccinimide (NIS) mediated ring opening of carbohydrate-derived donor-acceptor cyclopropanes with free ``CO2H'' group of N-protected L-amino acids at ambient conditions afforded iodo derivatives of glycosyl ester of L-amino acids. The iodides were subsequently converted easily into corresponding azides using NaN3 in DMF followed by reduction with Zn/AcOH to produce ester linked glycosyl amino acids. A similar strategy was adopted to synthesize C-linked glycoamino acid derivatives from different N-protected L-amino alcohols. By using an orthogonal strategy C- and O-linked glycopeptides were also synthesized

Synthesis of Thieno-Fused Five- and Six-Membered Nitrogen and Oxygen Heterocycles via Intramolecular Heteroannulation of 4,5-Substituted 3‑Amino or 3‑Hydroxy 2‑Functionalized Thiophenes

Diverse general high-yield routes for novel thieno-fused five- and six-membered nitrogen and oxygen heterocycles such as thieno­[3,2-<i>b</i>]­pyrroles, thieno­[3,2-<i>b</i>]­furans, thieno­[3,2-<i>b</i>]­indoles, thieno­[3,2-<i>b</i>]­benzofurans, thieno­[3,2-<i>b</i>]­pyridine-5-ones, thieno­[3,2-<i>b</i>]­pyran-5-ones, thieno­[3,2-<i>b</i>]­isoquinolin-5-ones, thieno­[3,2-<i>b</i>]­chromen-5-ones, thieno­[3,2-<i>b</i>]­quinolin-9-ones, and thieno­[3,2-<i>b</i>]­chromen-9-ones have been developed via in situ or stepwise intramolecular heteroannulation of newly synthesized 4,5-substituted 3-amino- or 3-hydroxy 2-functionalized thiophenes. These substituted 3-amino/hydroxythiophenes were readily obtained in high yields from easily accessible precursors, in a sequential one-pot process, by treatment of a range of (het)­aryl/unsubstituted acetonitriles or acetates with (het)­aryl dithioesters in the presence of LDA, followed by in situ alkylation–intramolecular condensation of the resulting enethiolate salts with functionalized activated methylene halides. The functionalized activated methylene halides employed in these reactions for the synthesis of various thieno-fused heterocycles were cinnamyl bromide, 2-bromobenzyl chloride, bromocrotonate, 2-(bromomethyl)­benzoate, and 2-chlorophenacyl bromide. A few of the 4,5-substituted 3-amino/hydroxy-2-stryrylthiophenes (or 2-acrylates) displayed strong fluorescence, and their absorption/emission spectra have also been examined

Ring opening of activated cyclopropanes with NIS/NaN3: synthesis of C-1 linked pseudodisaccharides

NIS/NaN3 mediated ring opening of various donor-acceptor cyclopropanes has been investigated. The study shows the necessity of the donor oxygen lone pair in such ring opening reactions. This methodology has been utilized in the synthesis of C-1 linked pseudodisaccharides through the use of click chemistry. (C) 2013 Elsevier Ltd. All rights reserved

One-Pot Synthesis of 2‑(Het)aryl/alkyl-3-cyanobenzofurans from 2‑(2-Bromoaryl)-3-(het)aryl-3-(methylthio)acrylonitriles and Benzyl Carbamate

A one-pot synthesis of 2-(het)­aryl/alkyl-3-cyanobenzofurans has been reported. The overall sequence involves base-induced reaction of 2-(2-bromoaryl)-3-(het)­aryl-3-(methylthio)­acrylonitriles with benzyl carbamate, generating α-(het)­aroyl-α-(2-bromoaryl)­acetonitriles, which are in situ subjected to copper-catalyzed intramolecular <i>O</i>-arylation, furnishing the 2-(het)­aryl/alkyl-3-cyanobenzofurans in high yields. A probable mechanism for the base-induced cleavage of 2-(2-bromoaryl)-3-(het)­aryl-3-(methylthio)­acrylonitriles to α-(het)­aroyl-α-(2-bromoaryl)­acetonitriles in the presence of benzyl carbamate has been proposed

One-Pot Synthesis of 2‑(Het)aryl/alkyl-3-cyanobenzofurans from 2‑(2-Bromoaryl)-3-(het)aryl-3-(methylthio)acrylonitriles and Benzyl Carbamate

A one-pot synthesis of 2-(het)­aryl/alkyl-3-cyanobenzofurans has been reported. The overall sequence involves base-induced reaction of 2-(2-bromoaryl)-3-(het)­aryl-3-(methylthio)­acrylonitriles with benzyl carbamate, generating α-(het)­aroyl-α-(2-bromoaryl)­acetonitriles, which are in situ subjected to copper-catalyzed intramolecular <i>O</i>-arylation, furnishing the 2-(het)­aryl/alkyl-3-cyanobenzofurans in high yields. A probable mechanism for the base-induced cleavage of 2-(2-bromoaryl)-3-(het)­aryl-3-(methylthio)­acrylonitriles to α-(het)­aroyl-α-(2-bromoaryl)­acetonitriles in the presence of benzyl carbamate has been proposed