Oxoflavidin, a new phenolic compound isolated from the Himalayan orchid Coelogyne elata was shown to be 2,7-dihydroxy-9,10-dihydro-5H-phenanthro[4,5-bcd]pyran-5-one (2d) by spectral and chemical evidence. © 1984.

P L MAJUMDER

N DATTA

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

Structure of oxoflavidin, a 9,10-dihydrophenanthropyrone from Coelogyne elata

Phytochemistry

Isoflaccidinin and isooxoflaccidin, new phenanthropyrone derivatives, isolated from the orchid Coelogyne flaccida were shown to be 2,7-dihydroxy-6-methoxy-5H-phenanthro [4,5-bcd] pyran-5-one and 2,7-dihydroxy-6-methoxy-9,10-dihydro-5H-phenanthro [4,5-bcd] pyron-5-one, respectively, from spectral and chemical evidence. © 1992.

Isoflaccidinin and isooxoflaccidin, stilbenoids from Coelogyne flaccida

Flaccidinin, a new phenanthropyrone derivative, and oxoflaccidin, the corresponding 9,10-dihydro compound, were isolated from the orchid Coelogyne flaccida which also yielded the previously reported 9,10-dihydrophenanthropyran derivatives flaccidin and imbricatin. The structures of flaccidinin and oxoflaccidin were established from spectral evidence and by chemical correlation. © 1989.

Flaccidinin and oxoflaccidin, two phenanthrene derivatives of the orchid coelogyne flaccida

Flaccidin, a new 9,10-dihydrophenanthropyran derivative, was isolated from the orchid Coelogyne flaccida. It was shown to be 2,6-dihydroxy-7-methoxy-9,10-dihydro-5H-phenanthro[4,5-bcd]pyran mainly from spectroscopic evidence. © 1988.

Flaccidin, a 9,10-dihydrophenanthropyran derivative from the orchid Coelogyne flaccida

Agrostophyllin, a naturally occurring phenanthropyran derivative from Agrostophyllum khasiyanum

Gymnopusin, the first naturally occurring phenanthrene derivative having a hydroxyl group at C-9, was isolated from the orchid Bulbophyllum gymnopus. It was shown to be 7,9-dihydroxy-2,3,4-trimethoxyphenanthrene (1a) mainly from the spectral data of the compound and those of its diacetyl (1b) and dimethyl ether (1c) derivatives. © 1988.

A ring-B oxygenated phenanthrene derivative from the orchid Bulbophyllum gymnopus

Coelonin, A 9,10-dihydrophenanthrene from the orchids Coelogyne ochracea and Coelogyne elata

The structure of flavidin (1a), a modified 9,10-dihydrophenanthrene, isolated from the orchids Coelogyne flavida, Pholidota articulata and Otochilus fusca has been established on the basis of spectral data. © 1982, American Chemical Society. All rights reserved.

Journal of Natural Products

Flavidin, a novel 9,10-Dihydrophenanthrene derivative of the orchids Coelogyne flavida, Pholidota articulata and Otochilus fusca

Coelogin and coeloginin, two novel 9,10-dihydrophenanthrene derivatives of the high altitude Himalayan orchid Coelogyne cristata, have been shown to have the phenanthro[4,5-bcd]pyran structures (1a) and (1b), respectively, from spectral and chemical evidence.

Journal of the Chemical Society, Perkin Transactions 1

Coelogin and coeloginin: Two novel 9,10-dihydrophenanthrene derivatives from the orchid coelogyne cristata

The structures of isoflavidinin and iso-oxoflavidinin, two new modified 9, 10-dihydrophenanthrenes of the orchids Pholidota articulata, Otochilus porecta and O. fusca have been established. 13C NMR spectral analysis of isoflavidinin acetate was made to confirm its structure. © 1982.

Journal	Phytochemistry
Publisher	-
ISSN	0031-9422