New access to the 1H-pyrazolo[4,3-c]pyridine core from bis-acetylenic-N- benzoylhydrazones

Tetrahedron

Volumn 60, Issue 4, 2004, Pages 933-938

  Commeiras, Laurent ^a   Woodcock, Samuel C ^a   Baldwin, Jack E ^a   Adlington, Robert M ^a   Cowley, Andrew R ^a   Wilkinson, Peter J ^a  

^a UNIVERSITY OF OXFORD   (United Kingdom)

Author keywords

1H Pyrazolo 4,3 c pyridine; 3 Furylindazole; Angiotensin II antagonist; Pyrazole ring

Indexed keywords

1H PYRAZOLO[4,3 C]PYRIDINE; AMMONIA; HYDRAZONE DERIVATIVE; PYRIDINE DERIVATIVE; UNCLASSIFIED DRUG;

AQUEOUS SOLUTION; ARTICLE; CHROMATOGRAPHY; CYCLIZATION; PRIORITY JOURNAL; PROTON NUCLEAR MAGNETIC RESONANCE;

EID: 0348230594     PISSN: 00404020     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tet.2003.11.036     Document Type: Article

References (11)

1. Hun-Kung H., Shu-Hui J., Pei-Yin H., Yu-Chih L., Chien-Huang L., Che-Ming T., Wen-Sen L. Bio. Pharm. 66:2003;263. and ref. therein.
2. Straub A., Stasch J.-P., Alonso-Alija C., Benet-Buchholz J., Ducke B., Feurer A., Furstner C. Bioorg. Med. Chem. Lett. 11:2001;781. and ref. therein.
3. Hardy C.R. The chemistry of pyrazolopyridines. Advances in Heterocyclic Chemistry. Vol. 36:1984;Academic, London. p 343.
4. Townsend, L. B.; Wise, D. S. Bicyclic 5-6 systems: three heteroatoms 2:1. Comprehensive heterocyclic chemistry II; Pergamon: Oxford; 1996, Vol. 7, p 283.
5. Nuclephilic attack onto an activated acetylene via a 9-endo-dig cyclisation has been observed elsewhere, see for example, Deslongchamps P., Roy B.L. Can. J. Chem. 64:1986;2068.
6. Walton D.R.M., Waugh F. J. Organomet. Chem. 37:1972;45.
7. Stang P.J., Ladika M. Synthesis. 1981;29.
8. Rojahn C.A. Chem. Ber. 55:1922;291.
9. Daneshtalab M., Tehrani M.H.H. Heterocycles. 22:1984;1095.
10. The atomic coordinates for 19 are available upon request from the Cambridge Crystallographic Data Centre, University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (Deposit number CCDC 211595). The crystallographic numbering system differs from that used in the test; therefore any request should be accompanied by the full literature citation of this paper.
11. Proto-desilylation of trimethylsilyl-acetylenes under aqueous base is a known reaction, see for example Baldwin J.E., Adlington R.M., Wilkinson P.J., Marquez R., Adamo M.F.A. Heterocycles. 59:2003;81.