Samaderines

Samaderin B, (17 ,2A,5R,5a7 ,7a3, 113, lla3, llhR,14.5 )T,7,7tf,ll,ll ,117-hexahydro-l,ll-dihydroxy-8,lltf,14-tri-methyl-277-5tf,2,5-(methanoxymetheno)naphth[l,2-<7]oxepine-4,6,10(577)-trione, and samaderin C, (lR,2S,5R,5aR, 7aS, KXS, 113, 11 3, 1 HR, 14S)-7,7a, 10, ll,ll ,117-hexahydro-l, 10,11 -trihydroxy-8, ll ,14-trimethyl-277-5 , 2,5-(metha-noxymetheno)naphth[l,2- oxepine-4,6(177,577)-dione, were isolated from the seed kernels of Samadera indica and exhibit antifeedant activity against Spodoptera litura third-instar larvae <2003AXC416>. 

Quassinoids.—2 -AcetylgIaucarubine (98) and a new antineoplastic quassinoid, 13,18-dehydroglaucarubinone (99), have been isolated from Simarouba amara. The related 13,18-dehydroglaucarubol-15-isovalerate (100) has been reported from Ailanthus excelsa. The details of the crystal structural analyses of samaderin 7A (101), from Samadera indica, and 6-hydroxypicrasin B (102), from Soulamea species, have appeared. 

Until 1985 only three quassinoids with Cis skeleton had been isolated from Simaroubaceae species, Samaderine A (5) isolated from Samadera indica [7], and laurycolactone A (6) and B (7) isolated from Eurycoma longifolia Jack [8],... 

Only nine quassinoids possessing the C19 basic skeleton were isolated until 1985 samaderins B (11), C (12), D (13), an 3,4-dihydrosamaderin B (14) from the stem and leaves of Samadera indica, cedronin (15) and cedronolin (16) isolated from the fruits of Simaba cedron, eurycomalactone (17) and 5,6-dehydroeurycomalactone (18) from Eurycoma longifolia Jack, and shinjulactone B (19) isolated from Ailanthus altissima Swingle [1],... 

Four quassinoids, indaquassin C (197), samaderins C (12), B (11) and A (5), isolated from the seeds and bark of Samadera indica [113], were tested for insect antifeedant against the tobaco cutworm, Spodoptera litura. Indaquassin C (197) was the most effective antifeedant. 

The nematocidal activity of 38 quassinoids, C19 or C20 was measured by using a species of Diplogastridae (Nematoda) to develop lead parasiticides [114], From various quassinoids tested, samaderine B (11) displayed the most potent nematocidal activity with a minimum lethal concentration (MCL) of 2.0 x 10 5 M. 

The nematocidal activities of samaderine B (11) was 15-fold greater than that of albendazole (3.0 x 10"4 M), 10-fold greater than that of thiabendazole (2.0 x 10-4 M) and 7.5-fold greater than that of avermectin (1.5 x 10 4 M). Thus, samaderine B (11) may eventually be used as lead parasiticides. 

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