ABSTRACT
Chemical investigation of a sample of propolis originating from North-Western Cameroon led to the isolation of thirteen alk(en)ylphenols (1-13) (inseparable mixture) along with α-amyrin (14), ß-amyrin (15), lupeol (16), cycloartenol (17), mangiferonic acid (18), ambonic acid (19), mangiferolic acid (20), ambolic acid (21), isomangiferolic acid (22) and nine alk(en)ylresorcinols (23-31) (inseparable mixture). All compounds were identified following analysis of their spectroscopic data and comparison with previously published reports. Compounds (8), (12), (13) and (30) are new natural products. GC-MS analysis carried out on the alk(en)ylphenol and alk(en)ylresorcinol mixtures (dimethyl disulphide trimethylsilyl derivatives) revealed the presence of saturated and mono-unsaturated compounds with side chain lengths ranging from C11 to C19 and C15 to C19, respectively. The position of the double bond in mono-unsaturated derivatives was established from the characteristic fragments resulting from the cleavage of the bond between the two methylthio-substituted carbons. The most abundant compound in each mixture was 3-(12'Z-heptadecenyl)-phenol (10) and 5-(12'Z-heptadecenyl)-resorcinol (29). This study is the first to report the presence of triterpenes (except for lupeol) and phenolic lipids, including eighteen compounds previously unreported in bee glue, in an African sample.
Subject(s)
Lipids/chemistry , Phenols/chemistry , Propolis/chemistry , Triterpenes/chemistry , Cameroon , Gas Chromatography-Mass Spectrometry , Lipids/isolation & purification , Molecular Structure , Phenols/isolation & purification , Resorcinols/chemistry , Resorcinols/isolation & purification , Triterpenes/isolation & purificationABSTRACT
A new triterpenoid, madhunolic acid, along with the three known constituents stigmasterol, 4-hydroxymethyl benzoate, and hydroquinone were isolated from the fruit seeds of Madhuca latifolia. The structure of the new compound was elucidated as 2beta,3beta,23-trihydroxyurs-5,12,20-trien-28-oic acid (1) on the basis of spectral data and chemical evidence.
Subject(s)
Madhuca/chemistry , Seeds/chemistry , Triterpenes/isolation & purification , Magnetic Resonance Spectroscopy , Triterpenes/chemistryABSTRACT
Two pentacyclic triterpenoids have been isolated from the aerial parts of Lawsonia alba. The structures of the new constituents, named as lawsonic acid and lawsonin have been elucidated as 3 alpha-E-ferulyloxy-lup-20(29)-en-28-oic acid and 3 alpha-E-ferulyloxy-urs-11-en-13 beta-ol respectively through spectroscopic studies.
