Purine 6-chloro-2-amino-9-

Purine, 6-amino-2-benzyIoxy-9-methyI-hydrogenolysis, 5, 558 Purine, 2-amino-6-chloro-reactions, 5, 562 Purine, 6-amino-2,8-dichIoro-hydrogenolysis, 5, 563... 

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... 

Scheme 20 Examples of the 6-chloro-amino-fluoro displacement sequence on purines and purine nucleosides...

As with the purines, the replacement of chloro groups by amino groups has been one of the major building blocks of pyridopyrimidine chemistry, being employed in a great variety of reactions too numerous to catalogue fully, particularly in the piromidic and pipemidic acid fields. 

H-Pyrido[2,l-i]purine-9-carboxylic acid, 7-oxo-methyl ester, 5, 566 Pyrido[2,3-6]pyrazine, amino-nucleophilic attack, 3, 253 Pyrido[2,3-h]pyrazine, 6-chloro-reactions... 

Tetrazolo[l,5-c]pyrimidine, 8-amino-7-chloro-purine synthesis from, 5, 591 Tetrazolopyrimidines... 

Alkanoyl chlorides and chloroformates can be treated with potassium fluoride and benzyItriethylammonium chloride to obtain the respective alkanoyl fluorides or fluoroformates [62]. 2-Amino-6-chloro-9-(2,3,5-tri-0-acetyl-P-D-ribofurano-syl)purine is converted to the 2-amino-6-fluoro product with potassium fluoride and trimethylamme in dimethylformamide under rigorously anhydrous conditions [65] (equation 37)... 

Deamination or dechlorination of the prodrugs of the 6-amino or 6-chloro moiety of 2-amino-6-substituted purines that are key intermediates... 

A series of 2-amino-6-fluoro-9-(13-dihydroxy-2-propoxymethyl)purine mono and diesters has been synthesized, as potential prodrugs of ganciclovir, from 2-amino-6-chloro-9-(13-dihydroxy-2-propoxymethyl)purine <99JMC324>. 2-Amino-6-atylsulfanylpurines 78 can easily be prepared from guanine (77) in what is essentially a one-pot reaction <99T5239>. 

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