226386-40-9Relevant academic research and scientific papers
Facile synthesis of 6-aryl-1,3-dimethyl-5H-pyrimido-[4,5-b][1,4]diazepine-2,4(1H,3H)-diones
Taghavi-Moghadam, Shahriyar,Stumpf, Ruediger,Fischer, Helmut,Pfleiderer, Wolfgang
, p. 313 - 320 (1999)
A facile procedure for the preparation of 6-aryl-1,3-dimethyl-5H-pyrimido[4,5-b][1,4]diazepine-2,4(1H,3H)-diones 8, 9 from 6-amino-5-arylideneamino-1,3-dimethyluracils 1, 2 and triethyl orthoacetate (3) in a two-step reaction via 6-aryl-8-ethoxy-6,7-dihydro-1,3-dimethyl-5H-pyrimido[4,5-b][1,4]diazepine-2,4(1H ,3H)-diones 6, 7 is described. Condensation of 1 with diethoxymethyl acetate (10) resulted in the formation of (1,3-dimethyl-2,6-(1H,3H)-dioxopurin-7-yl)(phenyl)methyl acetate (11) and a small amount of 1,3-dimethyl-6-phenyl-pyrazino[2,3-d]pyrimidine-2,4(1H,3H)-dione (12). The structures of 6 and 11 were unambiguously confirmed by single-crystal X-ray diffraction analysis.
Treating psoriasis with transient pro-drug forms of xanthine derivatives
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, (2008/06/13)
Compounds of the formula: STR1 wherein R, which may be the same or different, represents a member selected from the group consisting of --CH3, --C2 H5, --C3 H7, iso--C3 H7, --C4 H9, iso--C4 H9, pentyl, benzyl, allyl, 2-hydroxyethyl, cyclohexyl, 2-isobutenyl, hydroxymethyl, 2-phenylethyl and -CH2 O-R2, wherein R2 is defined infra; wherein R1 represents a member selected from the group consisting of H, C1 -C7 straight or branched alkyl, CCl3, CBr3, CI3, STR2 CH3 O--CH2 --, (CH3)2 NCH2 --, STR3 wherein R3 represents a member selected from the group consisting of -OH, halogen (Cl, Br, I), --OCH3, -COOCH3, -NO2 and -OCOCH3 ; wherein STR4 and wherein R2 represents a member selected from the group consisting of STR5 wherein R4 is a member selected from the group consisting of C2 -C20 straight or branched alkyl (C3 -C7 preferred), --[--(CH2)m --], wherein m represents an integer of from 0 to 10, STR6 wherein R3 is defined as above, STR7 the residue of any naturally occurring amino acid, the residue of any N- substituted amino acid, wherein said substituent is any amino acid protective group cleavable via hydrogenolysis or hydrolysis (e.g., formyl, benzyloxy, carbonyl, t-butyloxycarbonyl), the residue of an N,N-C1 -C5 -dialkyl or cycloalkylamino acid, STR8 wherein n represents an integer of from 1-5 and R5 and R6 which may be the same or different represent C1 -C5 alkyl or together form a heterocyclic ring with the N atom to which they are attached (e.g., pyrolidine, piperidine, morpholine, piperazine, imidazoline, thiazolidine, isoxazolidine), imidazolyl, O-C1 -C8 alkyl, O-benzyl, O-phenyl and STR9 wherein n, R5 and R6 are defined as above; and wherein R2 further represents a member selected from the group consisting of straight or branched C1 -C20 alkyl, STR10 wherein n, R5 and R6 are defined as above, phenyl, tolyl, xylyl, and --SO2 --R7, wherein R7 is a straight or branched C1 -C20 alkyl useful in treating psoriasis in warm-blooded animals are provided.
