Isoarundinin-I and isoarundinin-II, two new stilbenoids, were isolated from the orchid Arundina bambusifolia which earlier afforded, besides arundinin [3,3′-dihydroxy-4-(p-hydroxybenzyl)-5-methoxybibenzyl], a number of other stilbenoids and a triterpenoid. The structures of isoarundinin-I and isoarundinin-II were established as 3′,5-dihydroxy-2-(p-hydroxybenzyl)-3-methoxybibenzyl and 3,3′-dihydroxy-2-(p-hydroxy-benzyl)-5-methoxy-bibenzyl, respectively, mainly from spectroscopic evidence. © 1994.

P L MAJUMDER

(NEE CHATTERJEE) S GHOSAL

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Phytochemistry

Agrostophyllinol and agrostophyllinone, two new triterpenoids, were isolated from the orchid Agrostophyllum brevipes. Agrostophyllinone was also isolated from another orchid Agrostophyllum callosum. The structures of agrostophyllinol and agrostophyllinone were established as 24-methylene-lanosta-9(11)-en-3β-ol (5a) and 24-methylene-lanosta-9(11)-en-3-one (5c), respectively, from spectral and chemical evidence. The above triterpenoids are of considerable biogenetic importance. © 2002 Elsevier Science Ltd. All rights reserved.

Triterpenoids from the orchids Agrostophyllum brevipes and Agrostophyllum callosum

Callosumin, callosuminin and callosumidin, three new stilbenoids, were isolated from the orchid Agrostophyllum callosum which earlier afforded, besides 4-hydroxy-3,5-dimethoxybenzoic acid, 10 other structurally related stilbenoids, viz. orchinol, 6-methoxycoelonin, imbricatin, flaccidin, oxoflaccidin, isooxoflaccidin, flaccidinin, agrostophyllin, callosin and callosinin. The structures of callosumin, callosuminin and callosumidin were established as 2,4,6,7-tetramethoxy-9,10 dihydrophenanthrene, 2,4,6,7- tetramethoxyphenanthrene and 2,7-dihydroxy-5-ethoxy(ax)-6-methoxy-9,10- dihydro-5H-phenanthro[4,5-bcd]pyran, respectively, from spectral and chemical evidence. Although in naming callosumidin the systematic numbering system has been adopted, for ease of comparison of the spectral results the phenanthrene numbering system for the compound and its structural analogues is used.

Three stilbenoids from the orchid Agrostophyllum callosum

Callosin and callosinin, two new stilbenoids, were isolated from the orchid Agrostophyllum callosum, which also afforded, 4-hydroxy-3,5-dimethoxybenzoic acid, orchinol, 6-methoxycoelonin, imbricatin, flaccidin, oxoflaccidin, iso-oxoflaccidin, flaccidinin and agrostophyllin of previously known structures. Callosin was also isolated from another orchid, Coelogyne flaccida. The structures of callosin and callosinin were established as 2,6-dihyroxy-4,7-dimethoxy-9,10- dihydrophenanthrene and 2,6,7-trimethoxy-9,10-dihydro-5H-phenanthro [4,5-bcd]pyran-5-one, respectively, from spectral and chemical evidence. For ease of comparison of the spectral data the phenanthrene numbering system is used in this paper. © 1995.

Stilbenoids from the orchids Agrostophyllum callosum and Coelogyne flaccida

Two stilbenoids from the orchid arundina bambusifolia

Cirrhopetalanthridin and cirrhopetalidinin, two new stilbenoids isolated from the orchid Cirrhopetalum andersonii, were shown to be 4,7-dihydroxy-2,3-methylenedioxy-9,10-dihydrophenanthrene and 3,2'-dihydroxy-5'-methoxy-4,5-methylenedioxy bibenzyl, respectively, from spectral and chemical evidence.

2 STILBENOIDS FROM THE ORCHID CIRRHOPETALUM-ANDERSONII

Cirrhopetalidin and cirrhopetalinin, two new bibenzyl derivatives, and 3,3'-dihydroxy-5-methoxybibenzyl (batatasin-III) were isolated from the orchid Cirrhopetalum andersonii. The structures of the new bibenzyls were established as 2',3-dihydroxy-3'-methoxy-4,5-methylenedioxybibenzyl and 3,3'-dihydroxy-4,5-methylenedioxybibenzyl, mainly from spectral evidence.

2 BIBENZYL DERIVATIVES FROM THE ORCHID CIRRHOPETALUM-ANDERSONII

Lusianthrin and lusianthridin, two new stilbenoids, were isolated from the orchid Lusia indivisa. The structures of lusianthrin and lusianthridin were established from detailed spectral and chemical evidence. © 1990.

Lusianthrin and lusianthridin, two stilbenoids from the orchid Lusia indivisa

Flavanthrin, the first dimeric 9,10-dihydrophenanthrene derivative, was isolated from the orchid Eria flava which also yielded the previously reported 9,10-dihydrophenanthrene coelonin (2a). The structure of flavanthrin was established as the 1.1'-dimer (1a) of its congener coelonin from spectral and chemical evidence. © 1988.

Journal	Phytochemistry
Publisher	-
ISSN	0031-9422