Purine 6-hydrazino

Purines, N-alkyl-N-phenyl-synthesis, 5, 576 Purines, alkylthio-hydrolysis, 5, 560 Mannich reaction, 5, 536 Michael addition reactions, 5, 536 Purines, S-alkylthio-hydrolysis, 5, 560 Purines, amino-alkylation, 5, 530, 551 IR spectra, 5, 518 reactions, 5, 551-553 with diazonium ions, 5, 538 reduction, 5, 541 UV spectra, 5, 517 Purines, N-amino-synthesis, 5, 595 Purines, aminohydroxy-hydrogenation, 5, 555 reactions, 5, 555 Purines, aminooxo-reactions, 5, 557 thiation, 5, 557 Purines, bromo-synthesis, 5, 557 Purines, chloro-synthesis, 5, 573 Purines, cyano-reactions, 5, 550 Purines, dialkoxy-rearrangement, 5, 558 Purines, diazoreactions, 5, 96 Purines, dioxo-alkylation, 5, 532 Purines, N-glycosyl-, 5, 536 Purines, halo-N-alkylation, 5, 529 hydrogenolysis, 5, 562 reactions, 5, 561-562, 564 with alkoxides, 5, 563 synthesis, 5, 556 Purines, hydrazino-reactions, 5, 553 Purines, hydroxyamino-reactions, 5, 556 Purines, 8-lithiotrimethylsilyl-nucleosides alkylation, 5, 537 Purines, N-methyl-magnetic circular dichroism, 5, 523 Purines, methylthio-bromination, 5, 559 Purines, nitro-reactions, 5, 550, 551 Purines, oxo-alkylation, 5, 532 amination, 5, 557 dipole moments, 5, 522 H NMR, 5, 512 pJfa, 5, 524 reactions, 5, 556-557 with diazonium ions, 5, 538 reduction, 5, 541 thiation, 5, 557 Purines, oxohydro-IR spectra, 5, 518 Purines, selenoxo-synthesis, 5, 597 Purines, thio-acylation, 5, 559 alkylation, 5, 559 Purines, thioxo-acetylation, 5, 559... 

Purine, 2,6-dithioxo-1,2,3,6-tetrahydro-dethiation, 5, 558 Purine, 8-ethoxy-synthesis, 5, 577, 596 Purine, 6-ethoxycarbonylmethyl-nucleoside synthesis, 5, 561 Purine, 8-ethoxy-7-methyl-synthesis, 5, 577 Purine, 9-ethyl-synthesis, 5, 593 Purine, 6-fonnyl-reactions, 5, 547 synthesis, 5, 593 Purine, 8-fonnyl-reactions, 5, 547 Purine, 2-fluoro-synthesis, 5, 597 Purine, 6-fluoro-alkylation, 5, 529 synthesis, 5, 563, 573 Purine, 6-fluoro-9-methyl-reactions, with ammonia, 5, 562 Purine, 6-furfurylamino- — see Kinetin Purine, 9-glycofuranosyl-synthesis, 5, 572 Purine, 2-glycosyl-synthesis, 5, 587 Purine, 8-glycosyl-synthesis, 5, 585 Purine, 9-glycosyl-synthesis, 5, 572 Purine, 8-halo-synthesis, 5, 598 Purine, 2-hydrazino-synthesis, 5, 593 Purine, 8-o -hydroxyethyl-synthesis, 5, 574... 

Der Ersatz einer Benzylthio-Gruppe in N-Heterocyclen wie z. B. Purin-Derivaten kann durch Erhitzen in waBrigem Hydrazin (- 6-Hydrazino-Derivat, 88%) und anschlieBendes Kochen in Wasser in Gegenwart von Raney-Nickel erfolgen (70%)1 z. B. ... 

Purine, 9-glycofuranosyl-synthesis, 5, 572 Purine, 2-glycosyl-synthesis, S, 587 Purine, 8-glycosyl-synthesis, 5, 585 Purine, 9-glycosyl-synthesis, 5, 572 Purine, 8-halo-synthesis, 5, 598 Purine, 2-hydrazino-synthesis, 5, 593 Purine, 8-a-hydroxyethyl-synthesis, 5, 574... 

H-Purin 2,6-Bis-[l-methyl-hydrazino]- E16a, 742 (Cl - NR-NH2) lH-Pyrazol l,3-Dimethyl-5-(3-guanidino-ureido)-4-nitroso- -(Hydro-4-methyl-benzolsulfo-nat) E8b, 562 l,3-(CH3)2-6-oxo — 1,6-H2 — <(pyrazolo[4,3-c]-1,2,5-oxadiazin) + R2NH ... 

H-Purin 3,7-Dimethyl-2,6-dioxo-8-[l-(2-hydroxy-ethyl)-hydrazino]-... 

H-Purin 7-(2-Amino-ethyl)-1,3-dimethyl-2,6-dioxo-8-hydrazino-1,2,3,4-tetrahydro- E16a, 684 (Br -> NH-NH2)... 

H-Purin 9-Arabinfuranosyl-8-(2,2-dimethyl-hydrazino)-6-hydroxy-E16a, 763 (OR - NH-NR2)... 

The simplest title compounds were synthetized from 2-hydrazino-3-methyl-8-R-purines 312 and nitrous acid under formation of cyclic 4-methyl-tetrazolo[l,5-u]-purin-9-one (313, R = H, alkyl, aryl) and not 2-azido-3-purine. The cyclic structure was corroborated by IR and H-NMR spectra. The IR spectrum did not show the band of an azido group. With respect to the presence of the N(3)-methyl in the starting compound, the annulation had to take place at bond a of the purine skeleton (85CPB3113) (Scheme 91). 

A similar method was applied when preparing exclusively the [5,1-/)]-isomer from 2-hydrazino-l-methylpurinone. A useful access involved the treatment of nitrous acid and 4-amino-2-hydrazinopyrimidine-5-carbohydrazide (315) giving 5-amino-6-azidocarbonyltetrazolo[l,5-u]pyrimidine 316. Subsequent heating and cyclization converted it to the corresponding isocyanate 317 and tetrazolo[5, l-a]purin-7-one 318, respectively (86H1899) (Scheme 92). 

A full account of the methods of direct synthesis of the previously inaccessible fervenulin 4-oxides, reported last year, " has appeared. Also noted last year was the value of 6-hydrazino-l,3-dimethyl-5-nitrosouracil (356) as a precursor in purine and pteridine syntheses. Extension of this work has now provided access to 3-aryl-fervenulins (357) and pyrimido[5,4-e]-as-triazines (358), as... 

Purine Synthesis. Aminopyrimidines and aminouracil derivatives can be converted into purines with diethyl azodicarboxylate in a number of closely related synthetic methods. Treatment of compound (1) with an aldehyde leads to the formation of imine (2), which is converted to purine (3) with DAD (eq 4). A number of researchers have applied variations of this approach. Treatment of 6-aminouracils or 6-aminopyrimidines (unsubstituted at the 5-position) with DAD leads to the initial formation of hydrazino Michael adducts. Treatment of these adducts with excess DAD leads to cyclization (eq 5). 

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