A xanthonoid is a chemical

natural phenol In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to eco ...

ic compound formed from the xanthone backbone. Many members of the Clusiaceae contain xanthonoids. Xanthonoid biosynthesis in cell cultures of '' Hypericum androsaemum'' involves the presence of a benzophenone synthase condensing a molecule of benzoyl-CoA with three

malonyl-CoA Malonyl-CoA is a coenzyme A derivative of malonic acid. Functions It plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis. Fatty acid biosynthesis Malonyl-CoA provides 2-carbon units to fatty acids and commi ...

yielding to 2,4,6-trihydroxybenzophenone. This intermediate is subsequently converted by a benzophenone 3′-hydroxylase, a cytochrome P450 monooxygenase, leading to the formation of 2,3′,4,6-tetrahydroxybenzophenone. Some examples are tomentonone, zeyloxanthonone and calozeyloxanthone isolated from the bark of '' Calophyllum tomentosum'', apetalinone A, B, C and D from ''

Calophyllum apetalum ''Calophyllum'' is a genus of tropical flowering plants in the family Calophyllaceae. They are mainly distributed in Asia, with some species in Africa, the Americas, Australasia, and the Pacific Islands. History Members of the genus ''Ca ...

'', gaudichaudione A, B, C, D, E, F, G, H, gaudichaudiic acid A, B, C, D, E, morellic acid and forbesione from ''

Garcinia gaudichaudii ''Garcinia morella'' is a species of tree in the family Clusiaceae found in India, and Sri Lanka. Common names *Assamese: Kũzi Thekera (কুঁঁজী ঠেকেৰা) * English: ''gamboge'' (Sri Lanka), ''gamboge'' ( India) *Tamil: '' ...

'', methylswertianin and bellidifolin from ''

Swertia punicea ''Swertia punicea'' is a plant species in the genus ''Swertia''. The xanthonoid A xanthonoid is a chemical natural phenolic compound formed from the xanthone backbone. Many members of the Clusiaceae contain xanthonoids. Xanthonoid biosynthesi ...

'' or psorospermin obtained from ''

Psorospermum febrifugum ''Psorospermum febrifugum'' is a flowering plant species in the genus ''Psorospermum'' occurring in Africa. It grows in open woodland over a wide range of altitudes. The inconspicuous flowers are fragrant, creamy-white and some 8mm in diameter. T ...

''. Cassiaxanthone can be found in '' Cassia reticulata''.

Cytotoxic Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa''). Cell physiology Treating cells ...

xanthones ( gambogin, morellin dimethyl acetal, isomoreollin B, moreollic acid, gambogenic acid, gambogenin, isogambogenin, desoxygambogenin, gambogenin dimethyl acetal, gambogellic acid,

gambogic acid Gambogic acid is a xanthonoid that is derived from the brownish or orange resin from ''Garcinia hanburyi''. ''Garcinia hanburyi'' is a small to medium-sized evergreen tree (up to approximately 15 m in height) with smooth grey bark. It is nativ ...

, isomorellin, morellic acid, desoxymorellin and hanburin) can be isolated from the dry latex of '' Garcinia hanburyi'' (gamboge tree).Cytotoxic xanthones from Garcinia hanburyi. Jun Asano, Kazuhiro Chiba, Masahiro Tada and Takao Yoshii, Phytochemistry, Volume 41, Issue 3, February 1996, Pages 815-820,

References

{{xanthonoid Xanthonoids Secondary metabolites