HETEROCYCLIC-COMPOUNDS FROM SUGARS .16. CYCLIZATION REACTIONS OF N-1-(GLYCOPYRANOSYLAMINO)GUANIDINES

Acetylation of N-1-(aldopyranosylamino)guanidines 2-4 with D-gluco, D- galacto, and L-arabino configuration gives rise to N-1-per(O-acetylgly copyranosylamino)-N-1, N-2, N-3-triacetylguanidines 5-7 in good yields , as already stated by Feather and coworkers [Carbohydr. Res., 267 (19 95) 17-25] for the gluco compound. The acylaminoguanidines prepared ha ve been cyclized under mild conditions (boiling in ethanol or treatmen t with cold 0.1 M sodium methylate solution) to afford no-N-1-glycopyr anosyl-5-methyl-1H-1,2,4-triazoles. The structure of these pyranosyl n ucleosides 9, 10, 12-14 is discussed using H-1 and C-13 NMR spectrosco py and mass spectrometry. (C) 1997 Elsevier Science Ltd.