Synthetic Utility of Enaminonitrile Moiety in Heterocyclic Synthesis: Synthesis of Some New Thienopyrimidines
- 18 February 2009
- journal article
- research article
- Published by Informa UK Limited in Phosphorus, Sulfur, and Silicon and the Related Elements
- Vol. 184 (3), 719-732
- https://doi.org/10.1080/10426500802266407
Abstract
The hitherto unknown 3-amino-5-bromo-4, 6-dimethylthieno [2, 3-b] pyridine-2-carbonitrile ( 4 ) was condensed with p-anisaldehyde affording the Schiff base ( 5 ). Acylation of the thienopyridine derivative ( 4 ) using freshly distilled acetic anhydride gave a mixture of mono and diacetyl derivatives ( 6 ) and ( 7 ). Condensation of ( 4 ) with triethylorthoformate yielded the ethoxymethyleneamino derivative ( 8 ), which was treated with hydrazine hydrate to give the hydrazide derivative ( 9 ), which in turn was converted to a triazolopyrimidine derivative ( 10 ) upon treatment with freshly distilled acetic anhydride. Thiation of ( 4 ) with carbon disulfide afforded the pyrimidine dithione derivative ( 11 ), which was alkylated with ethyl iodide to give the di-s-ethylpyrimidine derivative ( 12 ).On the other hand, treatment of ( 4 ) with formamide yielded the aminopyrimidine derivative ( 13 ), whereas its treatment by formic acid produced the thienopyrimidinone derivative (1 4 ). Chlorination of (1 4 ) with a mixture of phosphorus pentachloride and phosphorus oxychloride gave the chloropyrimidine derivative ( 15 ), which in turn afforded the hydrazide derivative ( 9 ) upon treatment with hydrazine hydrate. Hydrazinolysis of ethyl-3-amino-5-bromo-4,6-dimethylthieno[2,3-b]pyridine-2-carboxylate ( 17 ) gave the hydrazino derivative ( 18 ), which in turn was converted to 8-bromo-7,9-dimethyl-3-formylaminopyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4(3H)-one ( 19 ) and 8-bromo-3-diacetylamino-2,7,9-trimethylpyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4(3H)-one ( 20 ) upon treatment with formic acid and freshly distilled acetic anhydride, respectively.Keywords
This publication has 22 references indexed in Scilit:
- A Simple Synthesis of Some New Thienopyridine and Thienopyrimidine DerivativesMolecules, 2002
- Pyrido [2, 3-d]pyrimidines and Pyrimido[5′, 4′:5, 6]pyrido[2, 3-d]pyrimidines as New Antiviral Agents: Synthesis and Biological ActivityArchiv der Pharmazie, 2002
- 4-Hydroxycoumarin in heterocyclic synthesisIl Farmaco, 2000
- Synthesis of isomeric triazolopyrrolopyrimidinesJournal of Heterocyclic Chemistry, 2000
- Synthesis and evaluation of some new fluorinated hydroquinazoline derivatives as antifungal agentsIl Farmaco, 2000
- Synthesis of 7H‐tetrazolo[1,5‐c]pyrrolo[3,2‐e]pyrimidines and their reductive ring cleavage to 4‐aminopyrrolo[2,3‐d]pyrimidinesJournal of Heterocyclic Chemistry, 1998
- The reaction of 5‐aminoimidazole‐4‐carbohydrazides with orthoestersJournal of Heterocyclic Chemistry, 1985
- Factors which influence the formation of oxadiazoles from anthranilhydrazides and other benzoylhydrazinesJournal of Heterocyclic Chemistry, 1984
- A simple one-step synthesis of 3-amino-2,4(1H,3H)quinazolinedionesJournal of Heterocyclic Chemistry, 1984
- Apparatus for accurate determination of melting and freezing pointsAnalytical Chemistry, 1981