| malevamide d: isolation and structure determination of an isodolastatin h analogue from the marine cyanobacterium symploca hydnoides. | malevamide d (1), a highly cytotoxic peptide ester, and the known compound curacin d (5) were isolated from a hawaiian sample of symploca hydnoides. the structure of 1 was elucidated by spectroscopic analysis including nmr and high-resolution ms/ms. partial stereochemical assignments of 1 were made by chiral hplc analysis of acid and base hydrolysates. malevamide d (1) demonstrated toxicity against p-388, a-549, ht-29, and mel-28 cell lines in the subnanomolar range, while curacin d (5) was weak ... | 2002 | 11975485 |
| symplostatin 3, a new dolastatin 10 analogue from the marine cyanobacterium symploca sp. vp452. | symplostatin 3 (1), a new analogue of dolastatin 10 (2), has been isolated from a tumor selective extract of a hawaiian variety of the marine cyanobacterium symploca sp. vp452. compound 1 differs from 2 only in the c-terminal unit; the dolaphenine unit is substituted by a 3-phenyllactic acid residue. symplostatin 3 (1) possesses ic(50) values for in vitro cytotoxicity toward human tumor cell lines ranging from 3.9 to 10.3 nm. it disrupts microtubules, but at a higher concentration than 2, correl ... | 2002 | 11809057 |
| isolation of dolastatin 10 from the marine cyanobacterium symploca species vp642 and total stereochemistry and biological evaluation of its analogue symplostatin 1. | the potent antitumor agent dolastatin 10 (1) was originally isolated from the sea hare dolabella auricularia, and we now report its isolation from the marine cyanobacterium symploca sp. vp642 from palau. the chemically related analogue symplostatin 1 (2) has been reisolated from guamanian and hawaiian varieties of s. hydnoides and its total stereochemistry completed by determining the n,n-dimethylisoleucine unit to be l. symplostatin 1 (2), like dolastatin 10 (1), is a potent microtubule inhibit ... | 2001 | 11473421 |