ABSTRACT
Phytochemical investigation of the fruits of Vitex negundo var. cannabifolia led to the isolation of 22 compounds (1-22). Their structures were elucidated mainly by spectroscopic analysis and comparison with the literature data. Among them, compounds 1 and 2 were two new artificial lignans. Primary bioassay showed that the polymethoxyflavones 9-12 displayed moderate-to-weak cytotoxicity against human HepG2 and rat C6 cell lines, while the triterpenoids 13-17 exhibited significant brine shrimp lethality with LC50values of 7.5-29.4 µM.
ABSTRACT
Chemical investigation of the cultures of a sponge-derived fungus Simplicillium sp. YZ-11 led to the isolation of a new minor diketopiperazine alkaloid cyclo-(2-hydroxy-Pro-Gly) (1) and a natural lactone (S)-dihydro-5-[(S)- hydroxyphenylmethyl]-2(3H)-furanone (2), together with five known ergostane-type sterols (3-7). Their structures were established based on extensive spectroscopic methods ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC and HMBC) and optical rotation analysis.
Subject(s)
Ascomycota/chemistry , Diketopiperazines/chemistry , Porifera/microbiology , Alkaloids/chemistry , Alkaloids/isolation & purification , Animals , Diketopiperazines/isolation & purification , Lactones/chemistry , Lactones/isolation & purification , Molecular Structure , Sterols/chemistry , Sterols/isolation & purificationABSTRACT
Eight steroids, including five withanolides (1-5) and three other ergostane-type steroids (6-8), were isolated from the aerial parts of the halophyte Datura stramonium L., which were collected from the Yellow River Delta in China. Their structures were elucidated on the basis of extensive spectroscopic methods, especially 1D and 2D NMR techniques. Compounds 1 and 2 were new compounds and characterised as (22R)-27-hydroxy-7α-methoxy-1-oxowitha-3,5,24-trienolide and its 27-O-ß-d-glucopyranoside. Compound 3 was a new natural product and identified as (22R)-27-hydroxy-1-oxowitha-2,5,24-trienolide and isolated from nature for the first time.
