Axiphenylalaninium and axityrosinium, modified amino acids from the Mediterranean marine sponge Axinella polypoides.

Two new modified amino acids, axiphenylalaninium (1) and axityrosinium (2), along with four known metabolites, C2-alpha-D-mannosylpyranosyl-L-tryptophan (3), N3,5'-cycloxanthosine (4), palythine (5), and taurine, were isolated from the marine sponge Axinella polypoides collected in the Mediterranean Sea. The structures were determined by spectroscopic studies and confirmed by X-ray analysis and chemical modifications.

Sulfated steroids: ptilosteroids A-C and ptilosaponosides A and B from the Solomon Islands marine sponge Ptilocaulis spiculifer.

Three new pregnanes, ptilosteroid A (1), ptilosteroid B (2), and ptilosteroid C (3), and two new pregnane glycosides, ptilosaponoside A (4) and ptilosaponoside B (5), were isolated from the marine sponge Ptilocaulis spiculifer collected in the Solomon Islands. The structures were determined by spectroscopic methods. Biological tests of these compounds showed that they are not cytotoxic against KB cells.