@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:000310947900007, title = {Synthesis of isomeric corniculatolides}, journal = {Tetrahedron Letters}, volume = {53}, number = {47}, year = {2012}, month = {NOV}, pages = {6343-6346}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Synthesis of three natural macrolides 11-O-methylcorniculatolide A, 11-O-methylisocorniculatolide A and isocorniculatolide A is reported using a simple, straight forward and high-yielding route. The present synthesis confirms the assigned molecular structures and provides an access to sufficient quantities of the natural products for the biological evaluation. In addition, we have determined the anti-TB potential of the three natural compounds using Alamar-Blue assay (H(37)Rv) and found no significant inhibitory activity at 100 mu g/ml. Excellent yields, short sequence and useful SAR information are the highlights of the present work. (C) 2012 Elsevier Ltd. All rights reserved.

}, keywords = {Diaryl ether, Isocorniculatolide, Macrocyclization, Mitsunobu reaction, Total synthesis}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2012.09.010}, author = {Raut, Gajanan N. and Chakraborty, Kasturi and Verma, Priyanka and Gokhale, Rajesh S. and Reddy, D. Srinivasa} } @article { ISI:000345902500007, title = {Facile and convenient synthesis of (+/-)-Biotin via MgCl2/Et3N-mediated C-C coupling and mitsunobu reaction}, journal = {Synlett}, volume = {25}, number = {20}, year = {2014}, month = {DEC}, pages = {2879-2882}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A synthesis of (+/-)-biotin is described starting from simple starting materials viz. cyclohexanone and amino malonic acid ester. The key steps involved are MgCl2/Et3N coupling of amino malonic acid ester derivative and acid chloride, Mitsunobu reaction, ozonolysis, Staudinger reduction, novel urea formation, and subsequent dibenzylation. This approach is economical and involves high-yielding steps and simple reaction conditions.

}, keywords = {Appel reaction, biotin, Mitsunobu reaction, Ozonolysis, Staudinger reduction}, issn = {0936-5214}, doi = {10.1055/s-0034-1379365}, author = {Chavan, Subhash P. and Chavan, Prakash N. and Lasonkar, Pradeep B. and Khairnar, Lalit B. and Kadam, Appasaheb L.} }