@article { ISI:000234174800006, title = {Enantioselective synthesis of 1-azaspiro[5.5]undecane ring system of histrionicotoxin alkaloids from D(+)-glucose}, journal = {Heterocycles}, volume = {65}, number = {12}, year = {2005}, month = {DEC}, pages = {2901-2916}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Histrionicotoxins, the archetype of a group of spiropiperidine containing alkaloids from the brightly colored poison arrow frog Dendrobates histronicus native to the Amazon rain forests of Southern Columbia, was first isolated by Daly, Witkop and co-workers in 1971.1 They all share a common Iazaspiro[5.5]undecan-8-ol ring system with unsaturated C4 or C5 side chains at both the 2 and 7 positions. The nature and length of the side chains distinguish the different members of the histrionicotoxin family.

}, keywords = {chiron approach, domino reaction, Ring closing metathesis}, issn = {0385-5414}, author = {Bera, Smritilekha} } @article { ISI:000282106600012, title = {Synthetic view of an analogue of the spiro-beta-lactone-gamma-lactam ring in oxazolomycins and lajollamycin}, journal = {Synthesis-Stuttgart}, number = {19}, year = {2010}, month = {OCT}, pages = {3301-3308}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Herein, we describe a new synthetic strategy towards an analogue of the spiro-beta-lactone-gamma-lactam ring found in a class of potent antibiotics, the oxazolomycins and lajollamycin. The synthetic idea relies on the construction of two rings (beta-lactone and pyrrolidinone). The formation of the spiro-beta-lactone was accomplished by a crossed Cannizzaro reaction, while the 3,4-disubstituted pyrrolidinone ring was constructed by a titanium(IV) chloride mediated chelation-controlled double stereodifferentiating Crimmins aldol reaction of Garner{\textquoteright}s aldehyde.

}, keywords = {Crimmins aldol reaction, crossed Cannizzaro reaction, Garner{\textquoteright}s aldehyde, lactones, Mitsunobu reaction, pyrrolidine}, issn = {0039-7881}, doi = {10.1055/s-0030-1257872}, author = {Mondal, Dhananjoy and Bera, Smritilekha} } @article { ISI:000309850200004, title = {Asymmetric synthesis of a 12-membered macrolactone core and a 6-epi analogue of amphidinolide W from 4-pentenoic acid}, journal = {Tetrahedron-Asymmetry}, volume = {23}, number = {15-16}, year = {2012}, month = {AUG}, pages = {1170-1185}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A flexible and efficient asymmetric route to the synthesis of a 12-membered macrolactone core and a 6-epi analogue of amphidinolide W has been accomplished from commercially available 4-pentenoic acid. The successful generation of stereocenters was achieved by utilizing an Evans{\textquoteright} chiral auxiliary-based alkylation and aldol reaction. Other key reactions such as a Julia-Kocienski olefination, Kita{\textquoteright}s macrolactonization, ring closing metathesis (RCM) reaction, and Yamaguchi{\textquoteright}s esterification were significant for the construction of the macrolactone cores. (c) 2012 Elsevier Ltd. All rights reserved.

}, issn = {0957-4166}, doi = {10.1016/j.tetasy.2012.07.006}, author = {Chatterjee, Bhaskar and Mondal, Dhananjoy and Bera, Smritilekha} } @article {48058, title = {Regioselective synthesis of 1,4,5-trisubstituted 1,2,3-triazole derivatives from alpha,beta-unsaturated carbonyls}, journal = {European Journal of Organic Chemistry}, volume = {2022}, year = {2022}, month = {JUL}, pages = {e202200317}, type = {Article}, abstract = {

The copper-catalyzed oxidative azide-olefin cycloaddition (OAOC) reaction of differently substituted alpha,beta-unsaturated carbonyls with azides provided an efficient method for preparing biologically active 1,4,5-trisubstituted 1,2,3-triazoles. In this study, the cycloaddition reaction was found to be a simple and powerful method for constructing diverse mono- and bis-(1,4,5-trisubstituted 1,2,3-triazole) functionalized heterocyclic compounds in moderate to high yields with great regioselectivity. The XRD-analysis data of one of the bis-triazole derivatives supported the regioselectivity as well as the conformity of the method in the construction of the triazole nucleus. The preliminary antifungal profile against C. albicans was observed with cinnamaldehyde-based triazole derivatives demonstrating promising results.

}, keywords = {alpha, antifungal, beta-Unsaturated carbonyls, Cycloaddition, Dibenzalacetone, Triazole}, issn = {1434-193X}, doi = {10.1002/ejoc.202200317}, author = {Verma, Naimish K. and Bera, Smritilekha and Gonnade, Rajesh and Mondal, Dhananjoy} }