Trocheliophorin: a novel rearranged sesquiterpenoid from the Indian Ocean soft coral Sarcophyton trocheliophorum.

A novel rearranged sesquiterpenoid, trocheliophorin (1) has been isolated from the soft coral Sarcophyton trocheliophorum besides the known compounds, sarcophytin, methyl arachidonate, and two polyhydroxy steroids (24S)-24-methylcholestane-3beta,5alpha,6beta,25-tetrol-25-monoacetate and (24S)-24-methylcholestane-3beta,5alpha,6beta,25-tetrol. The structure of the new sesquiterpenoid was elucidated by a study of its spectral data.

A new spiroketal steroid from Gorgonella umbraculum.

A new spiroketal steroid (2) was isolated from the Indian Ocean gorgonian, Gorgonella umbraculum besides the known briarane diterpenoids, juncellin, umbraculides A and D. The new steroid was characterised as 22-acetoxy-3,25-dihydroxy-16-24,20-24-bisepoxy-(3beta, 16alpha, 20S, 22R, 24S)cholest-5-ene (2) by a study of its spectral data.

Juncins I-M, five new briarane diterpenoids from the Indian Ocean gorgonian Junceella juncea Pallas.

Five new diterpenoids, juncins I-M (1-5), of the briarane skeleton have been isolated from the Indian Ocean gorgonian Junceella juncea in addition to four known derivatives, gemmacolides A-C (6-8) and juncin H (9). The structures of 1-5 were established by the interpretation of spectroscopic data.

Agallochins J-L, new isopimarane diterpenoids from Excoecaria agallocha L.

The ethyl acetate extract of Excoecaria agallocha L. furnished three more new isopimarane diterpenoids, 11alpha,14alpha-dihydroxy-7,15-isopimaradien-3-one, agallochin J (1), 3alpha, 1alpha,14alpha-trihydroxyisopimara-7,15-diene, agallochin K (2) and 6alpha,14alpha,17-trihydroxy-7,15-isopimaradien-3-one, agallochin L.

Ceriopsins F and G, diterpenoids from Ceriops decandra.

Chemical examination of the ethyl acetate solubles of the CH(3)OH:CH(2)Cl(2) (1:1) extract of the roots of Ceriops decandra collected from Kauvery estuary resulted in the isolation of two more diterpenoids, ceriopsins F and G (1-2) and five known compounds, ent-13-hydroxy-16-kauren-19-oic acid (steviol, 3), methyl ent-16beta,17-dihydroxy-9(11)-kauren-19-oate (4), ent-16beta,17-dihydroxy-9(11)-kauren-19-oic acid (5), ent-16-oxobeyeran-19-oic acid (isosteviol, 6), 8,15R-epoxypimaran-16-ol (7). The structures of the new diterpenoids were elucidated by a study of their physical and spectral data as methyl ent-13,17-epoxy-16-hydroxykauran-19-oate (1) and ent-16-oxobeyeran-19-al (2).

Seco diterpenoids from Excoecaria agallocha L.

Chemical examination of the ethyl acetate solubles of the CH(3)OH:CH(2)Cl(2) (1:1) extract of the roots of Excoecaria agallocha L. collected from Godavary estuary resulted in the isolation of three more new diterpenoids, agallochins M-O (1-3). The structures of the new diterpenoids were elucidated by a study of their physical and spectral data as methyl ent-13-epi-8,13-epoxy-4,6alpha-dihydroxy-3,4-secolabd-14-en-3-oate (1), methyl ent-13-epi-8,13-epoxy-2,3-secolabd-14-en-2,11-olid-3-oate (2), and methyl ent-17-hydroxy-3,4-secokaura-4(19),15-dien-3-oate (3).

Ceriopsins A-D, diterpenoids from Ceriops decandra.

Chemical examination of the ethyl acetate solubles of the CH(3)OH:CH(2)Cl(2) (1:1) extract of the roots of Ceriops decandra collected from Kauvery estuary resulted in the isolation of four new diterpenoids, ceriopsins A-D (1-4). The structures of the new diterpenoids were elucidated by a study of their physical and spectral data as methyl 17-hydroxy-16-oxobeyeran-18-oate (1), methyl 16(R)-16,17-dihydroxybeyeran-18-oate (2), 1 beta,15(S)-isopimar-7-ene-1,15,16-triol (3), and 8,15(R)-epoxypimarane-1 beta,16-diol (4).

New beyerane and isopimarane diterpenoids from Rhizophora mucronata.

Chemical examination of the ethyl acetate extract of the roots of Rhizophora mucronata collected from Mangalore Coast resulted in the isolation of three more new diterpenoids, rhizophorins C-E (1-3) in addition to the two, rhizophorin A, (6R,11S,13S)-6,11,13-trihydroxy-2,3-seco-14-labden-2,8-olid-3-oic acid, and rhizophorin B, ent-3beta,20-epoxy-3alpha,18-dihydroxy-15-beyerene, recently reported. The structures of the new diterpenoids have been elucidated by a study of their physical and spectral data as 17-hydroxybeyer-15-en-3-one (1), 3beta,17-diacetoxy-15-beyeren-2-one (2) and 3beta,6alpha-diacetoxy-8(14),15-isopimaradien-2-one (3).

Ceriopsin E, a new epoxy ent-kaurene diterpenoid from Ceriops decandra.

A new epoxy ent-kaurene diterpenoid, ceriopsin E (1), has been isolated from the mangrove plant Ceriops decandra and its structure elucidated by spectral data and single-crystal X-ray analysis.

ent-Kaurane and beyerane diterpenoids from Excoecaria agallocha.

The roots of Excoecaria agallocha yielded four new diterpenoids, ent-3 beta,20-epoxy-3 alpha,6 alpha-dihydroxykaur-16-ene (agallochin F) (1), 3beta,20-epoxy-3 alpha-hydroxybeyer-15-ene (agallochin G) (2), 3 beta,20:15R,16S-diepoxy-3 alpha-beyeranol (agallochin H) (3), and 3 beta,20-epoxy-3 alpha,6 alpha-dihydroxy-18-nor-beyer-15-ene (agallochin I) (4), along with three known derivatives, 2-acetoxy-1,15-beyeradiene-3,12-dione (5), 2-hydroxy-1,15-beyeradiene-3,12-dione (6), and ent-kauran-16 beta-ol-3-one. The structures of 1-4 were determined by spectroscopic (NMR and MS) data interpretation.