New heteroyohimbine-type oxindole alkaloid from the leaves of Thai Mitragyna hirsuta

Abstract

A new oxindole alkaloid, isomitraphyllinol (1), was isolated from the leaves of Thai Mitragyna hirsuta, together with five known oxindole alkaloids (2-6). The structure of the new compound was determined by spectroscopic analysis.

Simultaneous analysis of mitragynine, 7-hydroxymitragynine, and other alkaloids in the psychotropic plant “kratom” (Mitragyna speciosa) by LC-ESI-MS

“…On the other hand, mitragynine, 7-OH-mitragynine, and the other three target alkaloids were not detected in the raw material of M. hirsuta (Table 3). Although this plant is a related species of M. speciosa, it was reported not to contain the major narcotic compounds to be found in M. speciosa [18].…”

The botanical origin of kratom (Mitragyna speciosa; Rubiaceae) available as abused drugs in the Japanese markets

“…Among them, Mt-1 to Mt-3 were collected at Chulalongkorn University, Thailand, and were identified as M. speciosa (Mt-1 and Mt-2) and M. hirsuta (Mt-3) by Dr. Sumphan Wongseripipatana. The phytochemical study of Mt-3 (M. hirsuta) has already been reported by Kitajima et al [8]. So, we separately treated them as a big leaf for Mt-1 and a small leaf for Mt-2 based on their leaf size.…”

Metabolite and Molecular Characterization of Mitragyna speciosa Identifies Developmental and Genotypic Effects on Monoterpene Indole and Oxindole Alkaloid Composition

“…1,24 These species accumulate either the oxindole alkaloid mitraphylline (Scheme 1) or the MIA mitraciliatine, but none produce mitragynine, which is unique to M. speciosa. 1,25 The various species of mitragyna have historically been identified by either floral or fruit morphology and further differentiated by DNA barcoding using the nuclear ribosomal internal transcribed spacers (ITS). 24 There is wide variation in alkaloidal profiles even among various M. speciosa cultivars, including cultivars with low mitragynine content in addition to accumulating mitraphylline, an MIA characteristic of other mitragyna species.…”

“…Despite the pharmaceutical importance of mitragynine and other indole and oxindole alkaloids produced in M. speciosa , the downstream steps of MIA biosynthesis in this species are only recently being uncovered . Other species of mitragyna, including M. hirsuta , M. rotundifolia , M. diversifolia , and M. parvifolia , are also used medicinally in various parts of the world to treat cough, hypertension, diarrhea, depression, fever, and pain. , These species accumulate either the oxindole alkaloid mitraphylline (Scheme ) or the MIA mitraciliatine, but none produce mitragynine, which is unique to M. speciosa . , The various species of mitragyna have historically been identified by either floral or fruit morphology and further differentiated by DNA barcoding using the nuclear ribosomal internal transcribed spacers ( ITS ) . There is wide variation in alkaloidal profiles even among various M. speciosa cultivars, including cultivars with low mitragynine content in addition to accumulating mitraphylline, an MIA characteristic of other mitragyna species. , Furthermore, quantitative characterization of MIAs in whole plants and developmental variation of MIAs have not been studied comprehensively in M. speciosa .…”