Study On The Indole Alkaloides In Melodinus Hemsleyanus And Tabernaemontana Yunnanensis

Objective To enrich the indole alkaloids in Melodinus hemsleyanus and Tabernaemontana yunnanensis.The total alkaloids parts of two Apocynaceae plants was systematically separated by classical chromatographic methods.Methods Using 90% methanol extract the crushed plant sample and then remove the solvent,Three parts(non-alkaloid part,total alkaloid part and water layer part)were obtained by acid-base extraction.In this study,the main compounds were separated and purified by a variety of column chromatography(silica gel column chromatography,ODS column chromatography,Sephadex LH-20 column chromatography and RPHPLC chromatography).The isolated compounds were confirmed by nuclear magnetic resonance spectroscopy and other modern spectroscopy techniques.Results 46 alkaloids were isolated and identified from the total alkaloids part of the two plants.They are mainly aspidosperma and iboga types monoterpene indole alkaloids,including six bis-indole alkaloids and six new onesConclusion Melodinus A,Tabernaemontana A,Tabernaemontana B,Tabernaemontana C,Tabernaemontana D and Tabernaemontana E were new compounds.It was found that the content of meloscandonine in Melodinus hemsleyanus was significant.Possessing 7.8 % of the total alkaloids.While in Tabernaemontana yunnanensis,the content of dregamine,epidregamine and ervatamine were significant.Possessing 6.7 %,16.9 %,8.6 % of the total alkaloids respectively...