<?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
</style></custom4></record><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%">Kumar, Ravindra</style></author><author><style face="normal" font="default" size="100%">Banerjee, Prabal</style></author><author><style face="normal" font="default" size="100%">Puranik, Vedavati G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">One-step stereospecific strategy for the construction of the core structure of the 5,11-methanomorphanthridine alkaloids in racemic as well as in optically pure form: synthesis of (+/-)-pancracine and (+/-)-brunsvigine</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%">Ring-closing metathesis</style></keyword><keyword><style  face="normal" font="default" size="100%">synthesis design</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%">AUG</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">24</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%">4571-4587</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The unique core structure of the complex pentacyclic 5,11-methanomorphanthridine has been constructed stereospecifically in one step by an intramolecular [3+2] cycloaddition of a non-stabilized azomethine ylide (AMY), generated by the sequential double desilylation of 14 using (AgF)-F-I as a one-electron oxidant. The formation of the single diastereomer in the key step is explained by the preferred transition state produced by endo attack of the AMY on the ``Re'' face of the dipolarophile. An asymmetric version of the cycloaddition using a chiral dipolarophile was applied to construct the core structure 68 with 63 % ee. This strategy was successfully applied to the formal synthesis of (+/-)-pancracine and the total synthesis of (+/-)-brunsvigine. An unprecedented and interesting skeletal rearrangement product 49 was observed during the attempted assembly of the E ring from 46 through Horner-Wadsworth-Emmons reactions. Mechanisms involving azetidinium salt formation or the Grob-type fragmentation are advanced to explain the observed rearrangement.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">24</style></issue><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">3.07</style></custom4></record><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%">Majumder, Binoy</style></author><author><style face="normal" font="default" size="100%">Pandey, Ganesh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synthesis of 2-azabicyclo[m.n.0]-alkanes and their application towards the synthesis of strychnos and stemona classes of 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%">amines</style></keyword><keyword><style  face="normal" font="default" size="100%">Grignard reaction</style></keyword><keyword><style  face="normal" font="default" size="100%">Michael addition</style></keyword><keyword><style  face="normal" font="default" size="100%">Natural products</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2020</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUL </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">2020</style></volume><pages><style face="normal" font="default" size="100%">3883-3888</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;2-Azabicyclo[m.n.0]alkane ring systems, the conceptual precursors towards the synthesis of Strychnos and Stemona classes of alkaloids, were synthesized from tert-butyl 2-(phenylsulfonyl)-7-aza-bicyclo[2.2.1]hept-2-ene-7-carboxylate by alkyl Grignard reaction and intramolecular cyclisation of the in situ generated ring opening product 2. The synthesized cis-hexahydroindole 3 and cis-octahydro-benzo[b]azepine 5 scaffolds were utilized to construct the advanced intermediates 25 and 35, respectively, towards the synthesis of the corresponding Strychnos and Stemona classes of alkaloids.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">25</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;2.889&lt;/p&gt;
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