New nitrogenous bisabolene-type sesquiterpenes from a micronesian marine sponge, axinyssa species

Chemical investigation of an Axinyssa species of sponge collected at Yap Island afforded three new nitrogenous sesquiterpenes, 1-3, together with the known compound 3-formamidotheonellin (4). The structures of compounds 1, 3, and 4 were confirmed by spectroscopic methods, and compound 2 was tentatively identified by comparison of its (1)H and (13)C NMR data with those of 1, 3, and 4 and (1)H decoupling experiments.