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Acid- or base-catalyzed acylation of 1-benzylwye (7) provided the 7-substituted derivatives 9, 10, and 11 in poor yields. Although the reactions of lithiated 7 with electrophiles gave the 2-substituted derivatives 14, 15, 17, 20, 21, and 22, lithiation of 1-benzyl-7-bromo-2-chlorowye (23) followed by treatment with Me2CHCH2CHO (13) successfully introduced a side chain at the 7-position to afford 1-benzyl-2-chloro-7-(1-hydroxy-3-methylbutyl)wye (24).Cyclization of 1-benzyl-3-methylguanine (5) with 3-bromo-2-butanone followed by catalytic hydrogenolysis afforded 7-methylwye (2b), the hypermodified base isolated from archaebacterial transfer ribonucleic acids. A more efficient route for the synthesis of 2b has been developed via a series of reactions : the Vilsmeier-Haack reaction of 7, reduction with NaBH4, and catalytic hydrogenolysis over Pd-C.

3,9-Dimethyl- and 3-methyl-9-ethyl-adenine have been synthesized from N′-alkoxy-1-alkyl-5-formamidoimidazole-4-carboxamidine (II) by reduction with LiAIH4 followed by cyclisation with ethyl orthoformate and removal of the alkoxy-group by catalytic hydrogenolysis.

An improved procedure for the synthesis of 3-methylguanine (4) from 2, 6-diamino-1-methyl-4-pyrimidone (1) is presented. Elemental analyses and ultraviolet (UV) and nuclear magnetic resonance (NMR) spectral data are presented for the compounds involved in the reaction sequence.

1-Benzyl- (IIIa), 1-(3-methyl-2-butenyl)-(IIIb), and 1-allyladenine (IIIc) were prepared in 77, % 44%, and 69% yield, respectively, by alkylation of adenosine (I) followed by heating the resulting 1-substituted adenosine hydrobromides (IIa, b, c) in acetic acid.

The effect of the N6-methoxy group on regioselectivity in methylation of all five possible isomers of N-methyladenine has been investigated. The methoxyl group attached to all these isomers orients methylation to a considerable extent to nitrogen(s) in the same pyrimidine or imidazole moiety that the original N-methyl group is attached to. On the basis of the results of the present methylation study, 7,9-dimethyladeninium perchlorate has been synthesized from 7- or 9-methyl-N6-methoxyadenine.

The first synthesis of the antitumor antibiotic guanine 7-oxide (VI) has been achieved via a 4-step route starting from phenacyl bromide (I) and the nitropyrimidone III and proceeding through the intermediates IVe and Ve.

Bei der alkalischen Spaltung der N,N-Diethyl-dialkyl-adeniniumiodide (I) erhalt man die Imidazole (II) und (III).

[ R -( R *, S *)]-e-Hydroxywybutine ( 6 ) and its [ S -( R *, S *)]-isomer ( 9 ) have been synthesized as the most probable alternatives for hydroxy-Y base isolated from rat liver phenylalanine tRNA.

On the basis of the chiral syntheses of (1′R)-I and (1′S)-I and of their 9-ribosides (1″R)-III and (1″S)-III from D- and L-alanines, the structures of the cytokinins 1′-methylzeatin and its 9-riboside have been established to be (1′R)-I and (1″R)-III.

A convenient method for the synthesis of 1-alkyltryptophans is described. The proof of ind. -N-alkylation was obtained from several data. Effect of 1-alkyl substitution of indole was observed on the ultraviolet spectra of 1-alkytryptophans. It was confirmed by debenzylation of L-1-benzyltryptophan in liquid ammonia that no racemization had occurred in the alkylation. 1-Alkyltryptophans were converted to hydrazides via methyl ester hydrochlorides in good yields.

3-Methylisoguanosine (4c) has been synthesized from 5-(cyanomethylamino)-1(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)imidazole-4-carboxamide (1b) through the carbonitrile (2b).

Treatment of 5-(methylamino)-1-β-D-ribofuranosylimidazole-4-carboxamide (3) with CNBr followed by cyclization and reaction with bromoacetone gave 3-β-D-ribofuranosylwye (2) whose glycosidic bond was cleaved rapidly in acidic or alkaline solution, but was fairly stable at pH 5–8·5 at 37 °C.

The glycosidic bond of 3-β-D-ribofuranosylwye (1) has been found to undergo not only hydrogen ion catalysed cleavage but also general base catalysed or nucleophilic cleavage; steric assistance has been shown to account for its unusual susceptibility to acid.

3,9-Dimethyl- and 3-methyl-9-ethyl-adenine have been synthesized from N′-alkoxy-1-alkyl-5-formamidoimidazole-4-carboxamidine (II) by reduction with LiAIH4 followed by cyclisation with ethyl orthoformate and removal of the alkoxy-group by catalytic hydrogenolysis.