Three new diterpenoids isolated from Euphorbia nematocypha Hand.-Mazz and their anti-fungal activity.

Three new diterpenoids, named nematocynine A-C (1-3), together with twelve known compounds (4-15) were isolated from the aerial part of Euphorbia nematocypha Hand.-Mazz (Hereinafter referred to E. nematocypha). Their structures were elucidated by detailed spectroscopic analysis and comparison with literature data. In addition, all the compounds were tested for their anti-candida albicans activities used alone or in combination with fluconazole against sensitive strain and resistant strain in vitro. Wherein only compound 11 shows weak activity against candida albicans resistant strain (MIC50 = 128.15 µg/mL) when used alone. Compounds 1, 4, 7, 8, 9, 10, 12, 13 and 15 in combination with fluconazole showed potent anti-fungal activities (MIC50 = 15 ± 5 µg/mL, FICI = 0.05 ± 0.04) against the Candida albicans resistant strain SC5314-FR. The synergistic effects were weaker against the Candida albicans resistant strain SC5314-FR when the compounds 2, 3, 5 and 14 were combined with fluconazole (FICI = 0.16 ± 0.06).

Ten new prenylated flavonoids from Macaranga denticulata and their antitumor activities.

Ten new prenylated flavonoids, named denticulains A-J (1-10), together with seven known prenylated flavonoids (11-17) were isolated from Macaranga denticulata. Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with literature data. In addition, compounds 1 and 14 inhibited the proliferation of SW620 and HCT-116 cell lines with an IC50 value of 46.08 µM and 56.83 µM, respectively.