@article { ISI:000256839100021, title = {Stereoselective synthesis of beta-C-Allyl- and beta-C-propargyl-D-arabinofuranosides}, journal = {Synthesis-Stuttgart}, number = {11}, year = {2008}, month = {JUN}, pages = {1783-1787}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

The stereoselective synthesis of beta-configured C-allyl- and C-propargyl-D-arabinofuranosides (4,7-anhydro-1,2,3-deoxy-D-gluco-oct-1-enitols and -oct-1-ynitols) was addressed by employing allylation/propargylation of a dialdofuranose under aqueous Barbier reaction conditions and acid-catalyzed furan ring transposition of 5-O-mesyl-manno-oct-7-eno- or 5-O-mesyl-manno-oct-7-ynofuranoside derivatives.

}, keywords = {Allylation, Barbier reaction, C-glycoside, D-mannose, propargylation, Ring transposition}, issn = {0039-7881}, doi = {10.1055/s-2008-1067016}, author = {Ramana, C. V. and Narute, Sachin B. and Gonnade, Rajesh G. and Patil, Rahul S.} } @article { ISI:000286862200021, title = {Concise enantioselective synthesis of (+)-goniodiol and (+)-8-methoxygoniodiol via Co-catalyzed HKR of anti-(2SR, 3RS)-3-methoxy-3-phenyl-1, 2-epoxypropane}, journal = {Tetrahedron Letters}, volume = {52}, number = {3}, year = {2011}, month = {JAN}, pages = {438-440}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A short, enantioselective synthesis of (+)-goniodiol and (+)-8-methoxygoniodiol, cytotoxic styryllactones, has been achieved in high optical purities (99\% ee). The strategy employs Co-catalyzed HKR of racemic anti-(2SR, 3RS)-3-methoxy-3-phenyl-1,2-epoxypropane and Lewis acid-mediated diastereoselective allylation of aldehyde as chiral inducing key reactions. (C) 2010 Elsevier Ltd. All rights reserved.

}, keywords = {Allylation, diastereoselectivity, Hydrolytic kinetic resolution, Racemic anti-epoxide, Styryllactones}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2010.11.085}, author = {Kiran, I. N. Chaithanya and Reddy, R. Santhosh and Suryavanshi, Gurunath and Sudalai, Arumugam} } @article { ISI:000297732400016, title = {Enantioselective total syntheses of (-)-isonitramine, (-)-sibirine, and (+)-nitramine by ring-closing metathesis}, journal = {European Journal of Organic Chemistry}, number = {36}, year = {2011}, month = {DEC}, pages = {7372-7377}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

Concise enantioselective total syntheses of naturally occurring 2-azaspiro[5,5]undecan-7-ol (Nitraria) alkaloids viz. ()-isonitramine, ()-sibirine, and (+)-nitramine are accomplished in 42, 38, and 25?\% overall yield, respectively, in six steps starting from enantiomerically pure (S)-methyl 3-allyl-2-oxo-1,2,3,6-tetrahydropyridine-3-carboxylate (\>99?\%?ee). The key feature of the syntheses involves diastereoselective HosomiSakurai allylation followed by ring-closing metathesis.

}, keywords = {Alk-aloids, Allylation, Amino alcohols, Metathesis, Total synthesis}, issn = {1434-193X}, doi = {10.1002/ejoc.201101256}, author = {Pandey, Ganesh and Kumara, Prasanna C. and Burugu, Shiva Kumar and Puranik, Vedavati G.} } @article { ISI:000303429600017, title = {Formal synthesis of (-)-stemoamide using a useful epimerization at C-8}, journal = {Tetrahedron Letters}, volume = {53}, number = {21}, year = {2012}, month = {MAY}, pages = {2647-2650}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

The formal synthesis of (-)-stemoamide was achieved starting from L-pyroglutamic acid. The key steps used are the allylation using BF3 center dot OEt2, ring closing metathesis, allylic oxidation and a novel epimerization at C8. (C) 2012 Elsevier Ltd. All rights reserved.

}, keywords = {Allylation, Allylic oxidation, Pyroglutamic acid, Ring closing metathesis, Stemoamide}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2012.03.054}, author = {Chavan, Subhash P. and Harale, Kishor R. and Puranik, Vedavati G. and Gawade, Rupesh L.} } @article {45733, title = {Unified approach to fused and spirocyclic oxindoles through lewis-acid-promoted opening of spiroepoxyoxindoles with allylsilanes: application to the formal synthesis of (+/-)-physovenine}, journal = {European Journal of Organic Chemistry}, year = {2017}, month = {MAY }, pages = {2603-2609}, type = {Article}, abstract = {

A protocol for the construction of oxindoles containing all-carbon quaternary centres in a highly regioselective manner has been developed. The reaction involves opening of spiroepoxyoxindoles with allylsilanes to give Hosomi-Sakurai-type products as well as new silicon-containing spirocyclic oxindoles. A formal synthesis of (+/-)-physovenine was accomplished in five steps using this protocol.

}, keywords = {alkaloids, Allylation, annulation, Lewis acids, spiro compounds}, issn = {1434-193X}, doi = {10.1002/ejoc.201700259}, author = {Sharma, Brijesh M. and Yadav, Mahesh and Gonnade, Rajesh G. and Kumar, Pradeep} } @article {46628, title = {Apparent umpolung reactivity of indole through [Au]-catalysed cyclisation and lewis-acid-mediated allylation}, journal = {Chemistry-A European Journal}, volume = {26}, year = {2020}, month = {DEC}, pages = {17171-17175}, type = {Article}, abstract = {

The sequential functionalization of indole C2 and C3 in an umpolung fashion was executed with a predesigned substrate and choice of reagents. The developed method comprises gold-catalysed alkynol cycloisomerisation/intramolecular addition of C2 of indole and subsequent BF3.OEt2-mediated regioselective C3 allylation, resulting in the synthesis of the functionalized indoloisoquinolinone scaffold. The reaction involves 5-endo-alkynol cycloisomerisation and the dearomative addition of indole C2 to the intermediate oxocarbenium cation, which results in two equilibrating fused and spiropentacyclic intermediates, which upon treatment with allyl silane in the presence of BF3.OEt2, undergo selective indole C3 allylation. Other nucleophiles, such as hydride, azide and indole, were also found to be compatible with this process.

}, keywords = {Allylation, cyclization, domino reactions, Gold, umpolung}, issn = {0947-6539}, doi = {10.1002/chem.202003441, Early Access Date = NOV 2020}, author = {Shinde, Mahesh H. and Ramana, Chepuri V.} } @article {46941, title = {Concise enantioselective synthesis of (R)-(+)-goniothalamin oxide, a trypanocidal active agent via L-prolinol catalyzed asymmetric epoxidation of cinnamaldehyde}, journal = {Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry}, volume = {59}, year = {2020}, month = {MAR}, pages = {393-398}, type = {Article}, abstract = {

A short and straight-forward enantioselective synthesis of (R)-(+)-goniothalamin oxide 2 has been achieved with an overall yield of 39\% and 99\% ee. The synthetic approach involves L-prolinol catalyzed asymmetric epoxidation of cinnamaldehyde followed by Lewis acid-mediated diastereoselective allylation of epoxy aldehyde as the key chiral-inducing steps.

}, keywords = {Allylation, asymmetric epoxidation, Esterification, Grubbs{\textquoteright} catalyst, L-prolinol catalyst, Ring closing metathesis}, issn = {0376-4699}, author = {Kumar, B. Senthil and Mandle, Ram D. and Kamble, Sanjay P. and Sudalai, Arumugam} }