摘要:

AbstractTrifluoroacetonitrile was condensed with diethyl malonate to give a novel ethyl 2,6‐bis(trifluoromethyl)‐4‐hydroxypyrimidine‐5‐carboxylate (2) in 88% yield. Derivations of2are also

ISSN:0022-152X    

DOI:10.1002/jhet.5570260102

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractAlkylation of piroxicam with a homologous series of alkyl iodides gave reversibly formedO‐alkyl products1as well as unexpected, irreversibly formed zwitterionic compounds2, alkylated on the pyridine nitrogen, andO,N‐bis‐alkyl products3. Proof of structure was accomplished by nmr and X‐ray crystal analysis. Product distribution ratios were determined by hplc and are explained by the Hard‐Soft Acid‐Bas

ISSN:0022-152X    

DOI:10.1002/jhet.5570260103

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractThe β‐lactam antibiotic Tigemonam2undergoes desulfation to theN‐hydroxyazetidinone4, which rearranges to the isoxazolidin‐5‐one6. The structure of the rearrangement product6was confirmed by s

ISSN:0022-152X    

DOI:10.1002/jhet.5570260104

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractA novel synthesis of 3‐bromo‐1,2,4‐oxadiazoles by 1,3‐dipolar cycloaddition between bromocyanogen oxide and alkyl and aryl nitriles is de

ISSN:0022-152X    

DOI:10.1002/jhet.5570260105

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractThe Bischler‐Napieralski cyclization of the 1,2‐diaryiethylamides in a “one‐pot” process using ethyl poly‐phosphate as the reagent only yields the dihydroisoquinolines in certain cases. Thetrans‐stilbenes and in‐danes are obtained as neutral products and sometimes as sole products. Results clearly indicate the effect of aryl group substitution on the course of the reaction and the relationship between the Bischler‐Napieralski and

ISSN:0022-152X    

DOI:10.1002/jhet.5570260106

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractEthyl chromone‐2‐carboxylate and all its benzoanalogs were prepared and caused to react with 1,2‐diami‐nobenzene to give 2‐(2‐hydroxybenzoyl)methinyl‐3‐oxo‐1,2,3,4‐tetrahydroquinoxaline and its benzo analogs. The condensation products of diethyl oxalate and methyl hydroxyaryl ketones which were required for the preparation of the starting esters, were found to be subject to rin

ISSN:0022-152X    

DOI:10.1002/jhet.5570260107

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractO‐Alkylations of pyridoxine1and pyridoxamine5were carried out in acetone in the presence of sodium ethoxide and potassium iodide to give 5‐alkoxy‐6‐methyl‐3,4‐(bishydroxymethyl)pyridines2a‐jand 5‐alkoxy‐4‐aminomethyl‐6‐methyl‐3‐

ISSN:0022-152X    

DOI:10.1002/jhet.5570260108

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractAn example of the generalization of the synthesis of 8‐azahypoxanthinesAand 8‐azaadeninesB, interesting from a medicinal point of view, is presented by utilizing l‐amino‐2‐hydroxy‐3‐

ISSN:0022-152X    

DOI:10.1002/jhet.5570260109

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

AbstractPyridine‐3‐carboxamide (1) was reacted with alkyl radicals to give mono‐, di‐, and tri‐alkylated products. Thet‐butyl radical gives only 6‐t‐butylpyridine‐3‐carboxamide (4a). The reactivity decreases in the order oft‐butyl, isopropyl, and ethyl radicals. The product4areacts further with the 2‐phthalimidoethyl radical to give 2‐ and 4‐substituted products9and10, which were transformed into tetrahydronaphthy

ISSN:0022-152X    

DOI:10.1002/jhet.5570260110

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY

摘要:

Abstract1,3,8,10,12‐Pentazanaphthacene‐2,4,7,9(12H,3H,8H,10H)‐tetraones (linear pyrimidine‐fused 5‐deazaflavins) and 1,3,6,8,12‐pentazabenz[a]anthracene‐2,4,7,9(12H,3H,6H,8H)‐tetraones (bent pyrimidine‐fused 5‐deazaflavins) were synthesized by condensation of 7‐alkylaminoquinazoline with 6‐chloro‐5‐formyl‐3‐methyluracil. Also, their flavin analogs, 1,3,5,8,10,12‐hexazanaphthacene‐2,4,7,9(12H,3H,8H,10H)‐tetraones (linear pyrimidine‐fused flavins) and l,3,5,6,8,12‐hexazabenz[a]anthracene‐2,4,7,9(12H,3H,6H,8H)‐tetraones (bent pyrimidine‐fused flavins) were synthesized by cyclization of 7‐[N‐alkyl‐N‐(5‐nitrou

ISSN:0022-152X    

DOI:10.1002/jhet.5570260111

出版商:Wiley‐Blackwell    

年代:1989

数据来源: WILEY