Studies of Australian soft corals. XXIX. Several new cembranoid diterpenes from Nephthea brassica and related diterpenes from a Sarcophyton species

Abstract

The isolation of five known cembranoid diterpenes, (1), (2), (3), (4) and ( 5 ) , is reported from the soft coral Nephthea brassica. These diterpenes co-occur with several new but related diterpenes: (13S)-cembra-1,3,7,11-tetraen-13-ol (6) and its corresponding 13-acetate (7), 15-acetoxycembra-3,7,11-triene (8), (10S)-10,15-diacetoxy-7,8-epoxycembra-3,11-diene (9) and its corresponding 10-monoacetoxy derivative (10). Two related cembranoid diterpenes, (14S)-acetoxycembra-1,3,7,11-tetraene (15) and (14S)-cembra-1,3,7,11-tetraen-14-01 (16), are reported from a soft coral of the genus Sarcophyton.

Chemical diversity of Sarcophyton soft corals in Okinawa

“…In light of the seasonal variation on the amount of a cembrane in S. glaucum (Kashman et al 1974) and the occurrence of the same molecule in different species or even different families (Blackman et al 1982), the possibility of chemical taxonomy has been discussed (Coil 1992). However, our findings of compound 2 in most of the studied species and of the high diversity existing in S. glaucum/cinereum indicate chemical taxonomy as an unreliable method.…”

A New Norsesquiterpenoid from a Bornean Soft Coral Genus Nephthea

“…Soft corals of the genus Nephthea (Alcyonacea, Nephtheidae) contain a variety of bioactive metabolites such as sesquiterpenes, diterpenes and steroids [1,2,3,4,5,6,7,8,9,10,11,12,13], and they are widely distributed in the coastal waters of Sabah, Malaysia. However, there have been few reports on chemical investigation of Malaysian soft corals to date.…”

Secondary metabolites of a soft coral (Nephthea sp.) of the Bay of Bengal

“…N. chabrolii [3][4][5][6][7]14 , N. brassica, 8,15,16 N. tixera, 11 N. albida 11,12 , N. erecta 13 and other Nephthea spp. 9,10,[17][18][19][20][21][22] ) collected from various locations led to the isolation of varied extractives viz., sesquiterpenoids (guaianes 3,4,6,7,8,22 and eudesmanes 17,21 ), tetraprenylbenzenoids 9,21 , diphenylpropane-1,3-diol 10 , sterols (24-methylenecholesterols [11][12][13][14][15][16] ) and diterpenoids (bicyclic 6,22 , brassicolides, 8 xeniaphyllanes 17 , and cembranes [18][19][20]23,24 ). As a part of our search for bioactive components from marine sources a soft coral, Nephthea sp., was collected from the Bay of Bengal.…”