Three new triterpenoids, designated as genicunolide A (1), B (2) and C (3), along with friedelin (4) and friedelinol (5), were isolated from the aerial parts of Euphorbia geniculata. They were characterized as 1β-acetoxy-3β-hydroxy-11α,12α-oxidotaraxer-14-ene, 1β,3β-diacetoxy-21α-hydroxy-11α,12α-oxidotaraxer-14-ene and 3β,9α,20α-trihydroxy-Ψ-taraxast-5-ene, respectively, by spectral and chemica...

Reactive and hepatotoxic metabolites formed from the biotransformation of valproic acid (VPA) are normally detoxified by conjugating with GSH and followed by mercapturic acid metabolism to produce their respective N-acetylcysteine (NAC) conjugates. Hence, the levels of NAC conjugates of VPA in human urine are an indirect measure of exposure of the liver toward reactive metabolites of the antico...

An investigation of the natural products chemistry of the brown alga Sargassum asperifolium from the red sea yielded a new steroidal metabolite, 24-vinyl cholest-4-ene-24-ol-3-one, saringosterone (3), a known steroidal metabolite, 24-vinyl cholest-5-ene-3b,24-diol, saringosterol (4), and known diterpene with a hydroazulene skeleton, dictyone (1). The identification of the isolated metabolites w...

Abstract: 3-(Trifluoromethyl)prop-2-yne 1-iminium triflate salts were generated from 3-trifloxy-3-(trifluoromethyl)prop-2-ene by triethylamine-assisted elimination of triflic acid and trapped in situ various cycloaddition reactions. These included Diels-Alder reactions with 1,3-dienes, [2+2] 1,4-diphenylbuta-1,3-diene, [3+2] organoazides. All these revealed the excellent dienophilic dipolarophi...

A series of 5-hydroxy-1,4-naphthoquinones analogues was synthesized from juglone (6) and their antiproliferative activity against a representative panel of six human solid tumor cell lines has been investigated. The 2,5-dihydroxy-3-(3-methylbut-2-enyl)naphthalene-1,4-dione (4) and 2,3-dihydro-5-hydroxy-2-(prop-1-en-2-yl)naphtho[2,3-b]furan-4,9-dione (27) were the most potent antiproliferative a...

Microbial transformation of the anti-inflammatory steroid medrysone (1) was carried out for the first time with the filamentous fungi Cunninghamella blakesleeana (ATCC 8688a), Neurospora crassa (ATCC 18419), and Rhizopus stolonifer (TSY 0471). The objective was to evaluate the anti-inflammatory potential of the substrate (1) and its metabolites. This yielded seven new metabolites, 14α-hydroxy-6...