<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pandey, Ganesh</style></author><author><style face="normal" font="default" size="100%">Gupta, Nishant R.</style></author><author><style face="normal" font="default" size="100%">Gadre, Smita R.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Construction of the 5,10b-phenanthridine skeleton using [3+2]-cycloaddition of a non-stabilized azomethine ylide: total synthesis of (+/-)-maritidine and (+/-)-crinine alkaloids</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Organic Chemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alkaloids</style></keyword><keyword><style  face="normal" font="default" size="100%">Azomethine ylides</style></keyword><keyword><style  face="normal" font="default" size="100%">Cycloaddition</style></keyword><keyword><style  face="normal" font="default" size="100%">Natural products</style></keyword><keyword><style  face="normal" font="default" size="100%">Ylides</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">4</style></number><publisher><style face="normal" font="default" size="100%">WILEY-V C H VERLAG GMBH</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY</style></pub-location><pages><style face="normal" font="default" size="100%">740-750</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Vicinal quaternary and tertiary stereocenters of the 5,10b-phenanthridine skeleton 1 are constructed simultaneously in one step by the [3+2]-cycloaddition of non-stabilized azomethine ylide 9, generated by sequential double desilylation of 10 utilizing silver(I) fluoride as a one-electron oxidant. The regioas well as stereochemical origin of this cycloaddition reaction is explained through a favorable transition state 9''. The strategy is successfully applied for the total synthesis of the biologically active alkaloids (+/-)-maritidine (1a), (+/-)-crinine (1b), and their analogues (1d, 1e, and 1f).&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.07
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