Search Results

You are looking at 1 - 10 of 36 items :

  • "new ring system" x
Clear All

Pyrimidine Derivatives and Related Compounds, V Synthesis of Some Isoxazolo [2,3-a] pyrimidines. A New Ring System M o h a m e d H il m y E l n a g d i , E zzat M o h a m e d K a n d e e l , a n d K a m a l U s e f S a d e k Department of Chemistry, Faculty of Science, Cairo University, Cairo and Mansoura University at Elmansoura, A. R. Egypt (Z. Naturforsch. 32b. 311-314 [1977]; received August 31, 1976) Pyrimidine Derivatives, Isoxazolo[2,3-a]pyrimidines 3-Amino-5-phenyl-4-phenylazoisoxazole (1) reacts with ethyl acetoacetate to yield the corresponding

Pyrimidine Derivatives and Related Compounds, IX Preparation of 5-Am inopyrazolo[l,5-a] pyrimidines and of Oxazino[4,5 : 5,6] pyrazolo[l,5-a] pyrimidines, a New Ring System M o h a m e d H il m y E l n a g d i * , S h e r i f M a h m o u d F a h m y , M o h a m e d R i f f a a t H a m z a E l m o g h a y a r , a n d A r d a l l a M o h a m e d N e g m Department of Chemistry, Faculty of Science, Cairo University, Giza, A. R. Egypt (Z. Naturforsch. 32 b, 1478-1481 [1977]; received June 6 , 1977) Pyrimidine Derivatives Whereas the 5-aminopyrazole

Abstract

Utilising our earlier intermediate obtained by the umpolung reactivity of quinolizidine enamines, a new heterocyclic system: (11bSR, 15aSR)-1,2,3,6,11,14,15,15a-Octahydro-5H-indolo [2′,3′:3,4]pyrido[2,1-j]-1,6-naphthyridin-13(12H)-one was synthesised and its biological effects evaluated. Although modest, significant and selective effects were detected.

P atom of 3-chloro-triaza-3-phospha-5-borolidine (9) are readily achieved. Surprisingly, the various substituents at the P atom of the new heterocyclic systems have little in- fluence on <5nB, in contrast to 6 1 ! ! . This is attributed to n- and cr-effects. It is assumed that the new ring systems are nonplanar. He(I)-Photoelektronenspektren weisen im Verein mit CNDO/S-RechnungenPentamethyl-1.2.4-triaza- 2.5-diborolidin A eine planare Gerüststruktur zu [2]. Eine vorläufige Röntgenstrukturanalyse bestätigt dieses Ergebnis [3]. Demnach überwindet der

, can be transformed to several new ring-system containing molecules, which include 4,8,8-tri- methyl-9-methyleneperhydro-ll5-methanonaphthaleneI 4,8,8- trimethyl-9-methylene-1,2,4a,5,6,7,8,8a-octahydro-ll5-meth anonaphthalene, 8,8,9-trimethy1-4-methy1eneperhydro-1,3,5- -methanonaphthalene, 2,6,6,11-tetramethyltricyclo[5.4.0. O4'*]undecane, 2, 6,6,9-tetramethyltricycl0[5.4.O.O~~~]un- decane and 4,4,8,9-tetramethylperhydro-1,7-methanonaph- thalene derivatives. INTRODUCTION Longipinenes deserve their name from the parent hydrocarbon pinene (l), described as a

-pyrimidines, Australian J. Chem. 54 (2001) 69-74; DOI: 10.1071/CH00141. A. Z. M. S. Chowdhury, M. M. Matin and M. N. Anwar, Synthesis and antimicrobial activities of fused pyrimidines: Benzothieno[2,3- d ]imidazol[1,2-c]pyrimidine, Chittagong Univ. Stud. Part II 21 (1997) 79-83; ref Chem. Abstr. 130 (1999) 237530p. A. M. Abdel-Fattah, A. S. Aly, F. A. Gad, M. E. A. Zaki and A. B. A. El-Gazzar, A facile synthesis of isooxazolo[5,4:4',5']thiazolo[3,2- a ]thienopyrimidines, a new ring system, Phosphorus Sulfur 141 (1998) 263-281; DOI: 10.1080/10426509808033738. A. M. Abdel

. D. Gao Z. Preliminary report of control effect of triflunezopyrim on rice planthopper Hunan Agric. Sci 8 2017 61 63 11. Schmidt, A.; Shilabin, A. G.; Namyslo, J. C.; Nieger, M.; Hemmen, S.: Pyrimidine-annulated pyrrolobenzodiazepines. A new ring system related to aspergillus alkaloids. Eur. J. Org. Chem. 9 (2005) 1781–1789. Schmidt A. Shilabin A. G. Namyslo J. C. Nieger M. Hemmen S. Pyrimidine-annulated pyrrolobenzodiazepines. A new ring system related to aspergillus alkaloids Eur. J. Org. Chem 9 2005 1781 1789

lonidamine. J Heterocycl Chem. 1989; 26:613-618. Dattolo G, Cirrincione G, Almerico AM, Aiello E. Polycondensed nitrogen heterocycles. part22. pyrrolo[3,4-d]-1,2,3-triazines: a new ring system as potential antineoplastic agent. J Heterocycl Chem. 1989; 26(6):1747-1749. David KF. Preparation of 3-(azabicycloalkyl)-3, 4-dihydro-4-oxobenzotriazines and quinazolines as 5-HT 3 receptor antagonists. Chem Abst. 1990;112:7515m. Siegfried L, Guenther W, Thomas S, Helmut V, Renate G. Preparation of 8,9,10,11-tetrahydro- 1,2,3-triazino[4'5':4,5]-thieno[2,3-c] isoquinolines as

. Konshin, Synthesis and anti-inflammatory and analgesic activities of 2-arylamino-5,6,7,8-tetrahydroquinoline-3-carboxamides, J. Pharm. Chem. 22 (1988) 554-556; DOI: 10.1007/BF00763528. A. B. A. El-Gazzar, A. M. Gaafar, H. N. Hafez and A. M. Abdel-Fattah, Regioselective synthesis and reactions of polynuclear heterocyclic derived from pyrido[2,3- d ]pyrimidines, with new ring system, Phosphorus, Sulfur, Silicon 182 (2007) 369-403; DOI: 10.1080/10426500600919967. Guide for the Care and Use of Animals (Eds. E. D. Olfert, B. M. Cross and A. A. McWilliam), 2 nd ed, Vol

(11); 238(41); 225(5); 212(13); 197(22); 182(6); 170(7); 156(5); 141(55); 129(6); 115(10); 102(6); 91(11); 88(6); 76(7); 75(7); 64(10); 5(7); 48(51). CONCLUSIONS The new ring system III is formed by an intramolecular diazo-coupling forming a pyridazine ring. Such cyclization have also been reported in similar reaction12. ACKNOWLEDGMENT We would like to thank Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) and Coordenafäo de Aperfeifoamento de Pessoal de Nivel Superior (CAPES) for the continnous financial support. REFERENCES 1. Β. M. Lunch