Dysoxylum

Patel M, Nambiar S, Vaidayanathan P, Bheemanahally TR, Gudasalamani R, Kotiganahalli NG Ramesh V, John M, Thankayyan RS, Mishra PD, Viswakarma R, Ramanan US. (2010) Dysoxylum Binectariferum Hook.f (Meliaceae), a rich source of rohitukine. Fitoterapia 81 145-148. 

Anthothecol (94) and hirtin (95) have been interrelated via the trione (96). Dysobinin (97) is a new tetranortriterpenoid from Dysoxylum binectariferum7 An intermediate in a projected limonoid synthesis has been shown to have structure (98) by X-ray analysis. ... 

Two alkaloids possessing the 4-azaazulene skeleton have been isolated from leaves of Dysoxylum lenticellare (Meliaceae), namely 3-e/u-schelhamericine (188a) and dihydrohomoerysotrine (188b) (83MI2). For a report on Erythrina and related alkaloids, see (84MI1). 

Cedrela (cedrela) Dysoxylum (mahogany) Guarea (guarea)... 

Celtis kajewskii Men, et Perry/Light celtis Celtis luzonica Warb./Hard celtis Cryptocarya massoy (Oken.) Kosterm/Grytocarya Dracontomelum puberulum Miq./P.N.G. walnut Dysoxylum arnoldianum K. Schum./—... 

Dysoxylum gaudichaudianum 0uss.) Miq./— Elaeocarpus sphaericus (Gaertn.) K. Schum./... 

Of the simple phenethylisoquinoline alkaloids dysoxyline (8), (5)-(-t-)-homolaudanosine (9), and (-)-isoautumnaline (10), 8 and 9 were isolated from Dysoxylum lenticellare Gillespie (5). Alkaloid 10 was isolated from Colchicum ritchii R.B. (4). 

Although it is totally synthetic the model for the novel flavonoid structure of flavopiridol (42) is a natural product, rohitukine (43), the constituent responsible for anti-inflammatory and immunomodulatory activity isolated from Dysoxylum binectariferum Hook, f (Meliaceae). D. binectariferum is phylogenetically related to the Ayurvedic plant Dysoxylum malabaricum Bedd. used for rheumatoid arthritis. 

The Meliaceae is known as a family that produces a variety of secondary metabolites, and even of alkaloidal types, so the occurrence of chromone alkaloids is not predictable. Indeed, chromone alkaloids have been reported from one species only of Dysoxylum whilst other species of the same genus produce a different type of alkaloid. The occurrence of tubastraine, a derivative of rohitukine, from a species of coral, emphasises the unpredictability of the occurrence of this type of compound [10]. 

Rohitukine (7) has been synthesised by the group led by de Souza as part of their confirmation of the identity of the compound they isolated from Dysoxylum binectariferum [8]. An outline of the method used is shown in Fig. (4). It also followed a retrosynthetic scheme. 

Dysoxylum malabaricum stembark is used in traditional medicine in India for rheumatoid arthritis and bioassay guided fractionation for antiinflammatory activity of the stem bark of the related species D. binectariferum led to the isolation of rohitukine (7) as the major active component [16]. This compound showed good activity in a variety of animal models and led to the production of many analogues [13]. The most active of these could be termed flavonoids and are discussed above... 

An antiinflammatory cum immunomodulatory piperidinylbenzopyranone from dysoxylum-binectariferum-isolation, structure and total synthesis, Tetrahedron 1988, 44, 2081-2086. 

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