Abstract Two new glucosidic iridoids, designated as nishindaside ( 2a ) and negundoside ( 3a ), h... more Abstract Two new glucosidic iridoids, designated as nishindaside ( 2a ) and negundoside ( 3a ), have been isolated from the leaves of Vitex negundo ( Verbenaceae ). The absence of a C(3)–C(4) double bond and the presence of an equatorial 3-methoxy group in 2a , the 3-methoxy-3,4-dihydro derivative of agnuaide ( 1a ), were established from 1H and 13C NMR analyses, corroborated by mass spectral fragmentation of the hexaacetate ( 2b ). Negundoside ( 3a ) could be concluded to be the 2' -p-hydroxy benzoyl derivative of mussaenosidic acid from the results of alkiline hydrolysis and the shifts in the signals of C-1 ' , C-2 ' and C-3' in its 13C NMR spectrum.
Two new flavanoids, characterized as 5,3'-dihydroxy-7,8,4'-trimethoxyflavanone and 5,3'-dihydroxy... more Two new flavanoids, characterized as 5,3'-dihydroxy-7,8,4'-trimethoxyflavanone and 5,3'-dihydroxy-6,7,4'trimethoxyflavanone, have been isolated from the leaves of Vitex negundo.
Abstract Two new glucosidic iridoids, designated as nishindaside ( 2a ) and negundoside ( 3a ), h... more Abstract Two new glucosidic iridoids, designated as nishindaside ( 2a ) and negundoside ( 3a ), have been isolated from the leaves of Vitex negundo ( Verbenaceae ). The absence of a C(3)–C(4) double bond and the presence of an equatorial 3-methoxy group in 2a , the 3-methoxy-3,4-dihydro derivative of agnuaide ( 1a ), were established from 1H and 13C NMR analyses, corroborated by mass spectral fragmentation of the hexaacetate ( 2b ). Negundoside ( 3a ) could be concluded to be the 2' -p-hydroxy benzoyl derivative of mussaenosidic acid from the results of alkiline hydrolysis and the shifts in the signals of C-1 ' , C-2 ' and C-3' in its 13C NMR spectrum.
Two new flavanoids, characterized as 5,3'-dihydroxy-7,8,4'-trimethoxyflavanone and 5,3'-dihydroxy... more Two new flavanoids, characterized as 5,3'-dihydroxy-7,8,4'-trimethoxyflavanone and 5,3'-dihydroxy-6,7,4'trimethoxyflavanone, have been isolated from the leaves of Vitex negundo.
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