@article { ISI:000246298900004, title = {Practical formal synthesis of D-(+)-biotin from 4-formylazetidin-2-one}, journal = {Synthesis-Stuttgart}, number = {8}, year = {2007}, month = {APR}, pages = {1159-1164}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A practical synthesis of (3S,6R)-1,3-dibenzyltetrahydro-1H-furo[3,4-d]imidazole-2,4-dione, an important intermediate in the synthesis of biotin, from 4-formyl-3-mesyloxyazetidin-2-one has been achieved. Acid-catalyzed azetidin-2-one ring opening followed by a one-pot conversion of diamine hydrochloride to a cyclic urea and hydroxymethylene to chloromethylene by triphosgene to obtain (4S,5R)-methyl-1,3-dibenzyl-5-chloromethyl-2-oxoimidazolidine-4-carboxyl ate is the key step in this synthesis.

}, keywords = {azetidin-2-one, beta-Lactams, cyclization, Lactone, reduction}, issn = {0039-7881}, doi = {10.1055/s-2007-965992}, author = {Kale, Ajaykumar S. and Puranik, Vedavati G. and Deshmukh, Abdul Rakeeb A. S.} } @article { ISI:000259537800008, title = {Short enantioselective synthesis of (+)-L-733,060 via Shi epoxidation of a homoallylic carboxylate}, journal = {Tetrahedron Letters}, volume = {49}, number = {40}, year = {2008}, month = {SEP}, pages = {5736-5738}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A short and efficient enantioselective synthesis of (+)-L-733,060 in 92\% ee via Shi epoxidation of a homoallylic carboxylate is described. Johnson-Claisen rearrangement was employed to obtain the required carbon backbone, whilst intramolecular reductive O-to-N-ring expansion of a delta-azidolactone was used in the construction of the piperidine moiety. (C) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {1, 2-aminoalcohols, 3, 3-sigmatropic rearrangement, asymmetric epoxidation, Lactone}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2008.07.086}, author = {Emmanuvel, Lourdusamy and Sudalai, Arumugam} } @article { ISI:000283834100025, title = {Organocatalytic route to the synthesis of lactone moiety of compactin and mevinolin}, journal = {Tetrahedron Letters}, volume = {51}, number = {44}, year = {2010}, month = {NOV}, pages = {5838-5839}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

An efficient synthesis of lactone moiety of compactin has been achieved. The stereogenic centers were generated by means of iterative proline-catalyzed sequential alpha-aminoxylation and Horner-Wadsworth-Emmons (HWE) olefination of aldehydes. (C) 2010 Elsevier Ltd. All rights reserved.

}, keywords = {Aminoxylation, Compactin, Lactone, organocatalysis, Proline}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2010.08.093}, author = {Kumar, Pradeep and Pandey, Menaka and Gupta, Priti and Dhavale, Dilip D.} }