Alkaloids from Plants of Thailand

Isoquinolines and Isoquinoline-Derived Alkaloids from the Plants of Thailand... 

Leaves of Cinchona succirubra Pav. from a trial plantation in the north of Thailand have been reported to contain the typical bases of quinoline alkaloids (cinchonine, cinchonidine, quinidine, quinine, di-hydroquinidine, and dihydroquinine) together with the indole bases quina-mine and 3-epiquinamine (97,98). 10-Methoxycinchonamine (92) has also been isolated from this plant for the first time. Except for the inclusion of alkaloid 92, the alkaloid pattern in C. succirubra is the same as that in the cross-species C. succirubra x C. ledgeriana from Guatemala. 

This review will concentrate on work published in the last 20 years or so with the exception of a few background papers, since this is the period when most of the work on the chemistry of alkaloids from Malaysian plants have emerged. In writing this review we are mindful of the fact that it is somewhat artificial to suppose that flora ate respecters of national boundaries, hence the chemistry of the plants described in this chapter could very well be representative of similar flora found in other parts of the South East Asian region. In view of this, we will as far as possible and wherever appropriate, compare the occurrence of alkaloids with studies of similar plants from neighbouring countries, especially Thailand and Indonesia. 

Phillipson el al have also carried out an extensive survey of the alkaloidal content of this genus based on investigations of herbarium samples using TLC and GCMS [72]. Plants of this genus provide mainly heteroyohimbines, oxindoles and yohimbines. Chemical studies of several species from Thailand such as U. attenuata, U. canescans, U. elliplica, U. homomalla and U. macropylla have also been carried out by Phillipson and others [73-78]. A chemotaxonomic... 

Chapter 2, by Toh-Seok Kam is a review of alkaloids derived from Malaysian flora. Malaysia s position near the Equator confers on it a tropical climate characterized by high temperatures, humidity, and rainfall, conditions favorable for plant life that has resulted in a rich flora of about 15,000 species of higher plants. This review concentrates on work published during the past twenty years and where appropriate compares the occurrence of alkaloids with studies of similar plants from countries neighboring to Malaysia, especially Thailand and Indonesia. 

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