DISTRIBUTION OF IRIDOIDS IN DIFFERENT POPULATIONS OF PHYSOSTEGIA-VIRGINIANA AND SOME REMARKS ON IRIDOIDS FROM AVICENNIA-OFFICINALIS AND SCROPHULARIA-NINGPOENSIS
R. Nass et H. Rimpler, DISTRIBUTION OF IRIDOIDS IN DIFFERENT POPULATIONS OF PHYSOSTEGIA-VIRGINIANA AND SOME REMARKS ON IRIDOIDS FROM AVICENNIA-OFFICINALIS AND SCROPHULARIA-NINGPOENSIS, Phytochemistry, 41(2), 1996, pp. 489-498
Two subspecies of Physostegia virginiana from seven different origins
were investigated for iridoid glycosides. The plant material included
the authentic sources of 'deoxyloganic acid', isolated in 1970 by one
of the authors. This substance has now been identified as a 2.6:1 mixt
ure of 7-deoxy-8-epiloganic acid and 10-deoxygeniposidic acid. Additio
nally, we isolated 14 known compounds and three new iridoids: stegiosi
de I from P. virginiana ssp. virginiana (origin Freiburg) and stegiosi
des II and III from P. virginiana ssp. paemorsa (origin Chicago). The
distribution of 16 out of 20 iridoids, previously reported or now isol
ated from P. virginiana, was determined in all populations. The iridoi
d patterns were significantly different between the two subspecies. Th
e differences within ssp. virginiana were substantially smaller. The s
tructure of 'avicennioside', previously isolated from Avicennia offici
nalis, is revised to linarioside. Ningpogenin, previously isolated fro
m Scrophularia ningpoensis, is identical to a compound obtained by par
tial synthesis from aucubin.