Pyrrolodiazines

Pyrrolo[3,4-c][l,3]diazepine, dihydrosynthesis, 4, 287 Pyrrolo[l,3]diazepines synthesis, 7, 607 Pyrrolodiazines, 3-formyl-synthesis, 4, 511 Pyrrolo[3,2-c][l,2]dithioles occurrence, 6, 810... 

In an effort to explore the chemistry of pyrrolodiazines and their quatemized salts (see Section 6.2.2.2), Alvarez-Builla and co-workers prepared a series of pyrrolo[l,2-c]pyrimidines via methodology developed in their laboratory <99JOC7788>. Cyclocondensation of tosylmethyl isocyanide with substituted pyrrole-2-carboxaldehydes 17 produced pyrimidine derivatives 18 sifter removal of the tosyl group. The key to this procedure was the use of tosylmethyl isocyanide, which provided a relatively easily removed tosyl group in comparison to the more problematic decarboxylation of a carboxylic acid functionality. 

The 3-formyl derivatives of pyrrolopyridines and pyrrolodiazines are readily available (Section 3.09.3.2.2 and Scheme 22). They show typical aldehyde reactions, some of the more important of which are summarized in Schemes 23 and 24 (68AHC(9)27). 

J. P. Paoloni, Chem. Heterocycl. Compd. 30,1-116 (1977). Pyrrolodiazines with bridgehead nitrogen ... 

Pyrrolizidine chemistry, 5, 315 24, 247 Pyrrolizines, chemistry of, 37, 1 Pyrrolodiazines with a bridgehead nitrogen, 21, 1... 

Ethoxide ion attacks Oltipraz (86), a 1,2-dithiole-3-thione, at C(5), or possibly at C(3) <85T3705>. Ring opening and recyclization forms a pyrrolodiazine, isolated as the compound (87). With the bulkier r-butoxide ion, the attack is at C(4). 

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