Abstract
Bioassay directed fractionation of the methyl ethyl ketone extract of
Crescentia cujete resulted in the isolation of nine bioactive compounds, and
detailed spectroscopic interpretation led to the assignment of their structures
as (2S,3S)-3-hydroxy-5,6-dimethoxy dehydroiso-α-Iapachone [2.10], (2R)-5,6-
dimethoxydehydroiso-α-Iapachone [2.11], (2R)-5-methoxy dehydroiso-alapachone
[2.12], 5-hydroxy-2-(1'-hydroxyethyl)naphtho[2,3-b ]furan-4,9-dione
[2.13], 2-(1 '-hydroxyethyl)naphtho[2,3-b ]furan-4,9-dione [2.14]' 2-isopropenylnaphtho[
2,3-b ]furan-4,9-dione [2.15], 5-hydroxydehydro-iso-a-Iapachone [2.16],
3-hydroxymethylfuro[3,2-b ]naphtho[2,3-d]furan-5,10-dione [2.17], and 9-
hydroxy-3-hydroxymethylfuro[3,2-b ]naphtho[2,3-d]furan-5,10-dione [2.18].
Compounds 2.10-2.12 are new, showing selective activity towards DNA
repair-deficient yeast mutants. The selective DNA damaging activity of
known compounds 2.13-2.16 is reported herein for the first time. Compounds
2.17 and 2.18 also show DNA damaging activity, and possess a novel fused
ring system.
The bioactive sterols ergosta-5-24(28)-diene-3β,7α-diol [3.1] and 24,28-
epoxyergost-5-ene-3β,7α-diol [3.2], originally isolated from Pseudobersama
mossambicensis, have been synthesized from stigmasterol. In addition to
these sterols, some of their analogs were prepared, and the bioactivity of all
compounds were assessed.
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