Sesquiterpenes from the sponge Axinyssa isabela.

Further research on the constituents of the sponge Axinyssa isabela collected in the Gulf of California has led to the isolation of nine new sesquiterpenes, the eudesmanes axinisothiocyanates M and N (1, 2), the bisabolane axinythiocyanate A (3), and the aristolane derivatives axinysones A-E (4-8) and axinynitrile A (9), together with four known sesquiterpenoids (10-13). The structures of the new metabolites have been established by spectroscopic techniques.The absolute configuration of axinysones A (4) and B (5) has been assigned after esterification with (R)- and (S)-MPA acids. In addition, the unusual nitrile-containing sesquiterpene 9 has been synthesized from (+)-aristolone (14). The cytotoxic activity of the compounds isolated has been tested against three human tumor cell lines.

Cembrane diterpenes from the gorgonian Leptogorgia laxa.

The new cembrane diterpenes leptodienone A (2) and leptodienone B (3) and the known compounds lopholide, lophodiol B, lophodione, and lophotoxin (1) have been isolated from the gorgonian Leptogorgia laxa collected in the Gulf of California. The structures of the new metabolites have been established by spectroscopic techniques. The in vitro cytotoxicity of the new compounds has been tested against three human tumor cell lines.

Isothiocyanate sesquiterpenes from a sponge of the genus axinyssa.

The chemical study of a sponge of the genus Axinyssa collected in the Gulf of California has led to the isolation of the new bicyclic sesquiterpenes axinisothiocyanates A-L ( 1- 12) together with the known compounds (1 R,6 S,7 S,10 S)-10-isothiocyanato-4-amorphene ( 13), (4 R*,5 R*,7 S*,10 R*)-4-isocyanoeudesm-11-ene, (-)-epipolasin A, and (+)-aristolone. The structures of the new metabolites have been established by spectroscopic techniques, including the analysis of pyridine-induced 1H NMR chemical shifts. The cytotoxic activity has been tested against three human tumor cell lines.

Cytotoxic dibromotyrosine-derived metabolites from the sponge Aplysina gerardogreeni.

The chemical study of the sponge Aplysina gerardogreeni collected at the Gulf of California has led to the isolation of four new dibromotyrosine-derived metabolites, aplysinones A-D, whose structures were determined by spectroscopic analysis and chemical methods. The new compounds and four semisynthetic analogues prepared in this study have shown cytotoxic activity against human tumor cell lines.

Cembrane diterpenes from the gorgonian Lophogorgia peruana.

The chemical study of the gorgonian Lophogorgia peruana collected at the Gulf of California has led to the isolation of the new diterpenes lophodienone (2), lophodiol A (3), lophodiol B (4), 17-acetoxylophotoxin (5), 15,16-epoxylophotoxin (6), 17-acetoxy-15,16-epoxylophotoxin (7), and isoepoxylophodione (8), together with the known compounds lophotoxin (1), rubifolide (9), lopholide (10), deoxylophotoxin (11), and the lophotoxin analogues 12 and 13. The structures of the new metabolites have been established by spectroscopic techniques and chemical correlation. The in vitro cytotoxicity has been tested against three tumor cell lines.

Merosesquiterpenes from two sponges of the genus Dysidea.

The chemical study of two sponges of the genus Dysidea collected in the Gulf of California has led to the isolation of the new merosesquiterpenes 20-O-acetyl-21-hydroxy-ent-isozonarol (2), 20-O-acetylneoavarol (3), ent-yahazunol (4), and dysienone (5), together with the known compounds 1 and 6-9. The structures of the new metabolites have been established by spectroscopic techniques. The absolute configuration of compounds 5 and 6 has been investigated by application of a procedure developed by Riguera et al. Compounds 2 and 5 showed cytotoxic activity against three human tumor cell lines.