Cytosine analogue, a method of preparation of a cytosine analogue, a DNA methyltransferase 1 inhibitor, a method for DNA methylation inhibition, the use of the analogue in the treatment of diseases associated with deviations from normal DNA methylation

摘要

A cytosine analog, a method of preparation of a cytosine analog, a DNA methyltransferase 1 inhibitor, and a method for DNA methylation inhibition, is provided for the treatment of diseases associated with deviations from normal DNA methylation. The analog of cytosine may be comprised of 1, N4, 5 and 6-substituted derivatives of cytosine or 5,6-dihydrocytosine, wherein the analog can be described by the chemical formula;;
where R1 is H, R3, R4, 2′-deoxyribosyl, R4 is alkyl or aryl, X is N or C, wherein if X in the analog of formula I is N, then R5 is no substituent and if X in the analog of formula I and/or II is C or if X in the analog of formula II is N, then R5 and R6 are independently alkyl, aryl, hydroxyalkyl, aminoalkyl, hydroxyl, carboxyl, amino group, alkoxyl, aryloxyl, aminoalkyl, aminoaryl, thio group, sulfonyl, sulfinyl or halogen.

主权项

1. A method of preparation of an analogue of cytosine or a physiologically acceptable salt or a prodrug thereof, selected from the group consisting of 1, N4, 5 and 6 substituted derivatives of cytosine, 5-azacytosine, or 5,6-dihydrocytosine, wherein said analogue is described by the chemical formulas where
R1 is H, R4, or 2′-deoxyribosyl,R4 is alkyl or aralkyl,X is N in formula I or II, or X is C in formula I,
wherein with the proviso that if X in the analogue of formula I is N,
then R5 is no substituent and,wherein with the proviso that if X in the analogue of formula I is C or if X in the analogue of formula II is N,
then R5 and R6 are independently alkyl, aryl, hydroxyalkyl, aminoalkyl, hydroxyl, carboxyl, amino group, alkoxyl, aryloxyl, aminoalkyl, aminoaryl, thio group, sulfonyl, sulfinyl or halogen, wherein the method comprises: a) adding an N4-unsubstituted cytosine or an analogue thereof as defined above and an aromatic or an alkyl aldehyde in the quantity of 4-6 eq to anhydrous methanol or ethanol, b) introducing NaBH4 or BH3×SMe2 to the mixture in the amount of at least 1.1 eq relative to the aldehyde in order to reduce the obtained imine, c) neutralizing the reducing agent with hydrochloric acid, d) evaporating the mixture, e) pouring the mixture into water, f) extracting the mixture with ethyl acetate or butanol to obtain a mixture of alcohol and an N4-modified cytosine or an analogue thereof as defined above in ethyl acetate or butanol, g) obtaining a pure product by:
evaporating the separated organic layer to dryness to obtain the pure product or;extracting the separated organic layer with aqueous solution of an inorganic acid to obtain an aqueous solution of cytosine hydrochloride or other modified said N4-modified cytosine salt, depending on the acid added, where the resulting salt is free of alcohol, further comprising
1) neutralizing the solution with a hydroxide or other hydroxyl group donor,2) extracting the solution with ethyl acetate or butanol,3) at least one of freeze drying, evaporating, or a combination thereof the organic layer to obtain the pure product.