5-Aminoimidazole-4-carboxamide alkylations

Alkylations of 5-aminoimidazole-4-carboxamide (818) with 783 in acetonitrile and in the presence of triethylamine gave the two 1- and 3-isomers... 

Dacarbazine is a synthetic compound that functions as an alkylating agent following metabolic activation by liver microsomal enzymes by oxidative N-demethylation to the monomethyl derivative. This metabolite spontaneously decomposes to 5-aminoimidazole-4-carboxamide, which is excreted in the urine, and diazomethane. The diazomethane generates a methyl carbonium ion that is believed to be the likely cytotoxic species. Dacarbazine is administered parenterally and is not schedule-dependent. It produces marked nausea, vomiting, and myelosuppression. Its major applications are in melanoma, Hodgkin s disease, and soft tissue sarcomas. 

The following examples illustrate the scope of this reaction 3-aminopyr-role-2-carboxamide to a pyrrolo[3,2-d]pyrimidine-2,4-dione205 2-amino(IV-alkyl)benzamides to 3-alkyl-2,4-quinazoline-2,4-diones266 5-aminothiazole-4-carboxamide to thiazolo[5,4-d]pyrimidine-2,4-dione (see 149)236 4-aminoimidazole-5-carboxamide (and derivatives) to purine-2,6-diones (see... 

In some cases, purines are prepared from 4,5-disubstituted imidazoles by cyclocondensation with formic acid or its equivalents, e.g. the 9-alkylpurin-6(l//)-one 20 fi om l-alkyl-5-aminoimidazole-4-carboxamide 19 and formic acid ... 

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