著者

藤井 澄三 小川 和男 板谷 泰助 伊達 忠正 稲垣 甚一郎 野原 富士夫

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.43, no.3, pp.408-413, 1995-03-15 (Released:2008-03-31)

参考文献数

25

被引用文献数

2 3

---

A full account is given of the first syntheses of 6-mercaptopurine 7-N-oxide (4) and 6-methylthiopurine 7-N-oxide (5). The synthesis of 4 followed a "phenacylamine route", which started from condensation of 4, 6-dichloro-5-nitropyrimidine (15) with N-(4-methoxybenzyl)phenacylamine to form the phenacylaminopyrimidine derivative (11) and proceeded through conversion into the mercapto derivative, intramolecular cyclization between the NO2 nitrogen atom and the phenacyl carbanion to give 6-mercapto-9-(4-methoxybenzyl)purine 7-N-oxide (12), and removal of the 4-methoxybenzyl group. S-Methylation of 12 and removal of the 4-methoxybenzyl group afforded 5. The location of the oxygen function in 4, 5, and 12 was confirmed by X-ray crystallographic analysis of 5·H2O, which was shown to exist in the N(7)-OH form (19). A UV spectroscopic approach suggested that the neutral species of 4 exists in HO as the N(7)-OH tautomer (21), whereas that of 5 exists as an equilibrated mixture of the N(7)-oxide (5) and the N(7)-OH (19) tautomers. In the in vitro bioassay of antileukemic activity against murine L5178Y cells, the N-oxides 4 and 12 were found to be weakly cytotoxic.

著者

藤井 澄三 小川 和男 斎藤 徹 板谷 泰助 伊藤 忠正 岡村 公生

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.43, no.2, pp.321-324, 1995-02-15 (Released:2008-03-31)

参考文献数

26

---

Oxidation of 1-benzyladenine (12) with m-chloroperoxybenzoic acid in MeOH or in MeOH-0.5 M phosphate buffer (pH 6.6) has been found to afford 1-benzyladenine 7-oxide (13) as the main product. Nonreductive debenzylation of 13 gave adenine 7-oxide (14) in 63% yield. The structure of 13 was unequivocally established by an X-ray crystallographic analysis.

著者

/ 藤井 澄三 斎藤 徹 TOHRU SAITO

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.34, no.5, pp.2037-2043, 1986-05-25 (Released:2008-03-31)

参考文献数

28

被引用文献数

9 14

---

A detailed account is given of the final step of the general 7-alkalation procedure for adenine (1), which consists of the preferential benzylation at the 3-position of 1, regioselective alkylation of the resulting 3-benzyladenine (2) to give 7-alkyl-3-benzyladenine salts (3a-c), and debenzylation of 3a-c leading to 7-alkyladenines (4a-c). Debenzylation of 3a-c (X=Cl or ClO4) has been achieved by hydrogenolysis using hydrogen and Pd-C catalyst at atmospheric pressure, producing 7-alkyladenines (4a-c) in 38-74% yields. The use of the allyl or γ, γ-dimethylallyl group at the 3-position instead of the benzyl group for the synthesis of 7-methyladenine (4a) by this procedure has no practical value. Alternatively, the salts 3a-c (X=Br, ClO4, or I) have been debenzylated efficiently by treatment with conc. H2SO4 in the presence of toluene at room temperature for 3-6h or at 60°C for 0.5-2h, giving 4a-c in 73-93% yields.

著者

藤井 澄三 小川 和男 斎藤 徹 小林 恵子 板谷 泰助 伊達 忠正 岡村 公生

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.43, no.1, pp.53-62, 1995-01-15 (Released:2008-03-31)

参考文献数

49

被引用文献数

3 4

---

A detailed account is given of the first unequivocal synthesis of adenine 7-oxide (8). The synthesis started with peroxycarboxylic acid oxidation of 3-benzyladenine (6), readily obtainable from adenine (1) by benzylation, and proceeded through nonreductive debenzylation of the resulting 3-benzyladenine 7-oxide (7). The location of the oxygen function in 7 and 8 was confirmed by their chemical reactions including deamination and methylation and by X-ray crystallographic analysis. A UV spectroscopic approach suggested that the neutral species of 8 exists in H2O as an equilibrated mixture of the N(7)-oxide (8) and N(7)-OH (21) tautomers. Treatment of 6 with 30% aqueous H2O2 in MeOH in the presence of MeCN and KHCO3 at 30°C produced the N(7)-oxide 7 and 7-acetamido-3-benzyladenine (15) in 12% and 1% yields, respectively.

著者

小川 和男 西井 正廣 稲垣 甚一郎 野原 富士夫 斎藤 徹 板谷 泰助 藤井 澄三

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.40, no.5, pp.1315-1317, 1992-05-25 (Released:2008-03-31)

参考文献数

16

被引用文献数

2 7

---

The synthesis of 8-methylguanine 7-oxide (3) was accomplished via a "phenacylamine route", which started from condensation of α-(4-methoxybenzylamino)propiophenone (6), prepared by coupling of α-bromopropiophenone (4) and 4-methoxybenzylamine (5), with 2-amino-6-chloro-5-nitro-4(3H)-pyrimidinone (7) and proceeded through cyclization of the resulting phenacylaminopyrimidinone (8) and removal of the 4-methoxybenzyl group. The N-oxide 3 and its 9-arylmethyl derivatives 9 and 11 showed only very weak antileukemic activity and no antimicrobial activity.

著者

小川 和男 西井 正廣 稲垣 甚一郎 野原 富士夫 斎藤 徹 板谷 泰助 藤井 澄三

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.40, no.2, pp.343-350, 1992-02-25 (Released:2008-03-31)

参考文献数

47

被引用文献数

8 10

---

A full account is given of the first chemical synthesis of the antitumor antibiotic guanine 7-oxide (5) and its 9-substituted derivatives (24a-k and 26). Coupling of appropriate primary amines (17a-e, g-k) with phanecyl bromide (16) produced, after treatment with HCl, the corresponding N-substituted phenacylamine hydrochlorides (18a-e, g-k). A similar phenacylation of 4-amino-1-butanol (21) failed to give the desired compound 18f, so that 21 was heated with 2-bromomethyl-2-phenyl-1, 3-dioxolane (20) at 150-155°C for 3h to furnish, after treatment with HCl, the amino ketal hydrochloride 22 in 40% yield. Deketalization of 22 with hot 2N aqueous HCl afforded 18f in 96% yield. Condensations of the free bases, generated in situ from the hydrochlorides 18a-l and 1N aqueous NaOH, with the chloropyrimidinone 6 were effected in aqueous EtOH at the boiling point for 20 min or at 25-30°C for 3-24h, giving the 6-phenacylamino-4-pyrimidinones 19a-l in 54-90% yields. On treatment with 2N aqueous NaOH at room temperature for 10-60 min, the nitropyrimidinones 19a-k cyclized to provide the 9-substituted guanine 7-oxides 24a-k in 61-98% yields. A similar alkali-treatment of 19l failed to yield guanine 7-oxide (5). However, removal of the 9-(arylmethyl) group from 24i-k was effected with conc, H2SO4 at room temperature for 1-3h in the presence of toluene, producing the target N-oxide 5 in 56-89% yields. In the in vitro bioassay of antileukemic activity against murine L5178Y cells, none of the 9-substituted guanine 7-oxides (24a-k and 26) was more effective than the parent, natural N-oxide 5. Within this series, however, the benzyl analogues 24g-k with or without alkoxy functions were more cytotoxic, with IC50's of 13.0-48.0μg/ml, than the alkyl analogues 24a-f.

著者

藤井 澄三 高田 泰孝 小川 和男 板谷 泰助 松原 聰

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.43, no.2, pp.325-327, 1995-02-15 (Released:2008-03-31)

参考文献数

20

被引用文献数

2

---

Treatment of N6-benzyladenine (2) with 15% aqueous H2O2 in trifluoroacetic acid at 65-70°C for 1 h was found to give the N(3)-oxide (3) and the N(7)-oxide (4) in 4% and 4% yields, respectively. The structure of 3 was established by its identity with a sample prepared from 6-chloropurine 3-oxide (6) and benzylamine, and the structure of 4 by its identity with a sample obtained from 1-benzyladenine 7-oxide (8) by Dimroth rearrangement. The N-oxides 3 and 4, together with previously reported N6-benzyladenine 1-oxide (1), were tested for cytokinin activity in the tobacco callus bioassay. Each of the three N-oxides was active at 4 μM concentration, being less active than the parent base 2 by a factor of 40.

著者

小川 和男 西井 正廣 野原 富士夫 斎藤 徹 板谷 泰助 藤井 澄三

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.40, no.3, pp.612-616, 1992-03-25 (Released:2008-03-31)

参考文献数

46

被引用文献数

2 8

---

A detailed account is given of the first chemical synthesis of hypoxanthine 7-N-oxide (5), which started from coupling of 6-chloro-5-nitro-4(3H)-pyrimidinone (7) with N-(4-methoxybenzyl)phenacylamine, generated in situ from the hydrochloride (8), and proceeded through cyclization of the resulting phenacylaminopyrimidinone (9) and removal of the 4-methoxybenzyl group. The results of catalytic hydrogenolysis, methylation followed by catalytic hydrogenolysis, and rearrangement under acidic conditions of 5 supported the correctness of the assigned structure. An ultraviolet spectroscopic approach suggested that the neutral species of 5 exists in H2O mainly as the N(7)-OH tautomer (21). In the in vitro bioassay of antileukemic activity against murine L5178Y cells, 5 was weakly cytotoxic, with IC50 of 100μg/ml. It did not show any antimicrobial activity even at 1000μg/ml. None of the 9-(4-methoxybenxyl) (11) and O-methyl (12, 13, and 14) derivatives was found to be antiieukemic or antimicrobial.