𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Quinolone analogues 2. A facile synthesis of novel 3-substituted 1-alkyl-4-oxo-1,4-dihydropyridazino[3,4-b]quinoxalines

✍ Scribed by Yoshihisa Kurasawa; Kazunori Sakurai; Shinnosuke Kajiwara; Kazuho Harada; Yoshihisa Okamoto; Ho Sik Kim

Publisher
Journal of Heterocyclic Chemistry
Year
2000
Tongue
English
Weight
471 KB
Volume
37
Category
Article
ISSN
0022-152X

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The reaction of the 2‐(1‐alkylhydrazino)‐6‐chloroquinoxaline 4‐oxides 1a,b with diethyl acetone‐dicarboxylate or 1,3‐cyclohexanedione gave ethyl 1‐alkyl‐7‐chloro‐3‐ethoxycarbonylmethylene‐1,5‐dihydropyridazino[3,4‐b]quinoxaline‐3‐carboxylates 5a,b or 6‐alkyl‐10‐chloro‐1‐oxo‐1,2,3,4,6,12‐hexahydroquinoxalino[2,3‐c]cinnolines 7a,b, respectively. Oxidation of compounds 5a,b with nitrous acid afforded the ethyl 1‐alkyl‐7‐chloro‐3‐ethoxycarbonylmethylene‐4‐hydroxy‐1,4‐dihydropyridazino‐[3,4‐b]quinoxaline‐4‐carboxylates 9a,b, whose reaction with base provided the ethyl 2‐(1‐alkyl‐7‐chloro‐4‐oxo‐1,4‐dihydropyridazino[3,4‐b]quinoxalin‐3‐yl)acetates 6a,b, respectively. On the other hand, oxidation of compounds 7a,b with N‐bromosuccinimide/water furnished the 4‐(1‐alkyl‐7‐chloro‐4‐oxo‐1,4‐dihydropyridazino[3,4‐b]quinoxalin‐3‐yl)butyric acids 8a,b, respectively. The reaction of compound 8a with hydroxylamine gave 4‐(7‐chloro‐4‐hydroxyimino‐1‐methyl‐1,4‐dihydropyridazino[3,4‐b]quinoxalin‐3‐yl)‐butyric acid 12.

📜 SIMILAR VOLUMES

Quinolone analogues 1. A convenient synt
Quinolone analogues 1. A convenient synthesis of 1-alkyl-4-oxo-1,4-dihydropyridazino[3,4-b]quinoxaline-3-carboxylic acids
✍ Yoshihisa Kurasawa; Akiko Tsuruoka; Nanae Rikiishi; Noriko Fujiwara; Yoshihisa O 📂 Article 📅 2000 🏛 Journal of Heterocyclic Chemistry 🌐 English ⚖ 523 KB

## Abstract The reaction of the alkylhydrazinoquinoxaline __N__‐oxides **2a‐d** with dimethyl acetylenedicarboxylate gave the dimethyl 1‐alkyl‐1,5‐dihydropyridazino[3,4‐__b__]qumoxaline‐3,4‐dicarboxylates **3a‐d**, whose reaction with nitrous acid effected the C~4~‐oxidation to afford the dimethyl

ChemInform Abstract: Quinolone Analogues
ChemInform Abstract: Quinolone Analogues. Part I. A Convenient Synthesis of 1-Alkyl-4-oxo-1,4-dihydropyridazino[3,4-b]quinoxaline-3-carboxylic Acids.
✍ Yoshihisa Kurasawa; Akiko Tsuruoka; Nanae Rikiishi; Noriko Fujiwara; Yoshihisa O 📂 Article 📅 2001 🏛 John Wiley and Sons ⚖ 31 KB 👁 2 views

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v

Quinolone analogues 6 [1-5]. Synthesis o
Quinolone analogues 6 [1-5]. Synthesis of 3-halogeno-1-methylpyridazino[3,4-b]quinoxalin-4(1H)-ones
✍ Yoshihisa Kurasawa; Waka Satoh; Izumi Matsuzaki; Yuka Maesaki; Yoshihisa Okamoto 📂 Article 📅 2003 🏛 Journal of Heterocyclic Chemistry 🌐 English ⚖ 126 KB

## Abstract The reaction of the quinoxaline __N__‐oxides **7a,b** with diethyl ethoxymethylenemalonate gave the 1‐methylpyridazino[3,4‐__b__]quinoxaline‐4,4‐dicarboxylates **8a,b**, whose reaction with __N__‐bromosuccinimide or __N__‐chlorosuccinimide afforded the 3‐halogeno‐1‐methylpyridazino[3,4‐