Madagascar Periwinkle, Catharanthus

Vincamine, vinblastine and vincristine are very important clinic alkaloids. They are produced naturally by plants vincamine by Vinca minor, and vinblascine and vincristine by Madagascar periwinkle Catharanthus roseus). The vindoline synthesis pathway starts with strictosidine and, via dehydrogeissoschizine, preakuammicine, stemmadenine and tabersonine, is converted to vindoline and vincristine (Figure 42). Conversion from vindoline to vinblastine is based on the NADH enzyme activity. Vinblastine and vincristine are very similar alkaloids. The difference is that vincristine has CHO connected to N, whereas vinblastine in the same situation has only CO3. This synthetic structural differences influence their activity. Vinblastine is used to treat Hodgkin s disease (a form of lymphoid cancer), while vincristine is used clinically in the treatment of children s leukaemia. Vincristine is more neurotoxic than vinblastine. 

The Madagascar periwinkle Catharanthus roseus (= Vinca rosea) (Apocynaceae) is a small herb or shrub originating in Madagascar, but now common in the tropics and widely cultivated as an ornamental for its shiny dark green leaves and pleasant five-lobed flowers. Drug material is now cultivated in many parts of the world, including the USA, Europe, India, Australia, and South America. 

MADAGASCAR PERIWINKLE -- Catharanthus roseus, formerly Vinca rosea. Family Apocynaceae (Dogbane family). 

Madagascar periwinkle (Catharanthus roseus, family Apocynaceae)... 

Another prestigious institution, the University of Texas M.D. Anderson Cancer Center has been taken to task for claiming that well over 50% of people with cancer who are cared for at the Craita- return home cured (Epstein, 1998a, p. 475). This is as compared to other findings, for instance, about chemotherapy, which is described as merely a placebo for most patients, although the use of the so-called Vinca alkaloids (derived from the Madagascar periwinkle, Catharanthus roseus) have been successful in stopping blood-related cancers.)... 

The Madagascar periwinkle Catharanthus roseus, Apocynaceae, formerly known as Vmca rosea) is a small subshrub or herbaceous plant native to Madagascar. It contains about 130 monoterpene indole alkaloids of different subclasses (vanderHeijden et ah, 2004). Nowadays, C. roseus occurs worldwide in subtropical and tropical regions. It is cultivated as an ornamental plant, but it has also found application in the folk medicine of various countries. Because the plant was used as an antidiabetic in Jamaica, it was screened for hypoglycaemic activity by Eli-Lilly, USA, and the Cancer Research Center,... 

Based on a biogenetic hypothesis, the dimerization of vindoline and catharanthine into vinblastine (extracted from Madagascar periwinkle, Catharanthus roseus) [ROB 98], a synthetic scheme was developed using a crucial biomimetic coupling for the development of the molecule as a drug... 

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