摘要:

AbstractThe synthesis of derivatives of benzo[f]quinazoline, benzo[g]quinazoline and benzo[h]quinazoline is reviewed. Each class of compound is treated separately. The review covers ring formations as well as group modifications.

ISSN:0022-152X    

DOI:10.1002/jhet.5570130401

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractSeventeen derivatives of 2(1H)quinoxalinone and 2H‐l,4‐benzoxazin‐2‐one have been synthesized for structural study. All of the compounds having a substituted phenacyl, isonicotinoylmethyl, or 2‐furoylmethyl side chain are shown to exist in the enamine form with an internal chelation both in the crystalline and solution states as evidenced by the ir and pmr spectra, respectively. In the gas phase, however,o‐hydroxyphenacyl derivatives can exist in another type of intramolecularly hydrogen‐bonded form which is supported by their

ISSN:0022-152X    

DOI:10.1002/jhet.5570130402

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractNmr analysis was found to be superior to an older ir technique for assigning structures in a study involving ring contraction‐expansion of 3‐hydroxypiperidine ⇌ 2‐hydroxymethylpyrrolidine systems and their ester derivatives. Nmr was not useful in studies of 3‐aminopiperidines and 2‐aminomethylpyrrolidines, but it could be applied to certain of theirN‐acyl derivatives. The nmr method was used to determine that esterification reactions of 1‐methyl‐3‐(p‐toluenesulfonyl)‐piperidine and the sodium or potassium salts of some highly substituted carboxylic acids gave the ring‐contracted pyrrolidine esters. In contrast, 1‐methyl‐3‐aminopiperidine formed an amide with benzilic acid in which the piperidine ring remained unchanged. Aminolysis of methyl benzilate with 1‐methyl‐3‐aminopiperidine resulted in a novel decarbonylation of the ester and isolation of benzophenone

ISSN:0022-152X    

DOI:10.1002/jhet.5570130403

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractAroylphenylacetylenes reacted with ammonium dithiocarbamate and ammonium hydrogen sulfide in 60% dioxane‐waler mixture at 15° to give mainly a mixture of the corresponding β‐hydroxy‐α‐thiobenzoylstyrene derivatives (III) and (E,Z)‐β,β'‐di(α‐aroylstyryl) sulfides (IV), whereas with sodium xanthate and sodium sulfide they gave only (III). However, when benzoyl‐(Ia) orp‐ehlorobenzoyl‐(Id)phenylacetylenes was refluxed with ammonium dithiocarbamate in ethyl alcohol, it gave a mixture of (IIIa or d) and the (E,E)‐β,β'‐di(α‐aroylstyryl) sulfide (VIa or d).β‐Hydroxy‐α‐thiobenzoylstyrene derivatives (III), (E,Z)‐(IV) and (E,E)‐(VI)‐β,β'‐di(α‐aroylstyryl) sulfides reacted with hydrazine hydrate and phenylhydrazine to give 3(5)‐aryl‐5(3)‐phenyl‐(IX)‐ and 5‐aryl‐1,3‐diphenyl‐(X)pyrazoles, respectively. The former compounds (III) reacted with guanidine and ethyl hydrazinecarboxylate to give the corresponding aminopyrimidin

ISSN:0022-152X    

DOI:10.1002/jhet.5570130404

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractPyridoxol and pyridoxal on benzylation with dimethylphenylbenzylammonium hydroxide (“leucotrope”) gave 3‐O‐benzylpyridoxol (IV) and 3‐O‐benzylpyridoxal (V), respectively. As a possible mechanism of this reaction an ion pair intermediate has been postulated. Oxidation of IV and V with chromic oxide‐pyridine‐acetic acid complex gave 3‐O‐benzyl‐4‐pyridoxic acid lactone (VI), which could also be obtained by benzylation of 4‐pyridoxic acid. Treatment of VI with dimethylamine gave 2‐methyl‐3‐benzyloxy‐5‐hydroxymethylpyridine‐4‐N,N‐dimethylcarbox‐amide (X) which oxidized to form the 5‐formyl derivative (XI). The latter on hydrolysis yielded the metabolite, 2‐methyl‐3‐hydroxy‐5‐formylpyridine‐4‐carboxylic acid (I). When reacted with liquid ammonia, VI gave 3‐O‐benzyl‐4‐pyridoxamide (VII) which was then oxidized to give 2‐methyl‐3‐benzyloxypyridine‐4,5‐dicarboxylic acid cyclicimide(IX). Acid hydrolysis of IX gave another metabolite, 2‐methyl‐3‐hydroxypyridine‐4,5‐dicarboxylic acid (XIII), which could also be obtained by oxidizing XI with potassium permanganate in water to yield 2‐methyl‐3‐benzyloxy‐5‐carboxypyridine‐4‐N,N‐dimethylcarboxamide (XII) and subsequent hydrolysis with hydrochloric acid. A positional isomer of I, 2‐methyl‐3‐hydroxy‐4‐formylpyridine‐5‐carboxylic acid (XVII) was synthesized starting from 3‐O‐benzyl‐5‐pyridoxic acid lactone (XIV) following similar reaction sequences used for the preparation of I. Ring‐chain tautomerism has been studied in I, XVII, opianic acid (XVIII), phthalaldehydic acid (XIX) and (2‐carboxy‐4,5‐dimethoxy)‐phenylacetaldehyde (XX) in different solvents by nmr and in the solid state by ir spectroscopy. A direct and reliable differentiation between the open form (aldehyde proton in low field) and the ring form (lactol proton in the intermediate field) has been obtained by nmr spectroscopy. In sodium deuteroxide and pyridine‐d5the open chain form existed exclusively (except for homolog (XX) which is in cyclic form in pyridine‐d5), whereas in 18% hydrogen chloride in deuterium oxide all the compounds are completely in the cyclic form. In hexafluoroacetone hydrate‐d2, XVIII, XIX, and XX exist in the cyclic form whereas I is in the open form. In DMS0‐d6both cyclic and open‐chain forms have been observed in XVIII, XIX and XX. Definite peak assignment for the two forms could not be made in I due to broadening or superimposition with C6‐H. The metabolite I, isometabolite (XVII) and opianic acid (XVIII) form cyclic acetyl derivatives whic

ISSN:0022-152X    

DOI:10.1002/jhet.5570130405

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

Abstractl‐(2‐Aminophenyl)pyrrole (I) and l‐[2‐(aminomethyl)]phenylpyrrole hydrochloride (III) undergo cyclization reactions with aldehydes and ketones to form 4,5‐dihydropyrrolo[l,2‐a]‐ quinoxalines and 5,6‐dihydropyrrolo[l,2‐a][l,4]benzodiazepines, respectively. It was also found that the use of the free base of compounds corresponding to III do not cyclize directly but lead instead to the intermediate Schiff bases which are subsequently cyclized to the desired benzodiazepines by treatment with

ISSN:0022-152X    

DOI:10.1002/jhet.5570130406

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractThe synthesis of covalently linked porphyrin dimers and trimers is described. Mono‐ and dihydroxyporphyrins were synthesized by transeslerifying 5,10,15,20‐tetra(4‐carbomethoxy‐phenyl)porphyrin with ethylene glycol. The mixture of transesterified porphyrins were separated by preparative thin layer chromatography. Metal derivatives were made of the mono‐ and dihydroxyporphyrins and these were reacted with the acid chloride of a monocarboxyporphyrin to yield hybrid dimers and trimers containing one melalloporphyrin and either one or two free base porphyrins. The structures and purity of the dimers and trimers were established by measuring the absorbance spectra, nmr spectra, and molecular weight by gel permeation chrom

ISSN:0022-152X    

DOI:10.1002/jhet.5570130407

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractAnalogs of methotrexate diethyl ester (1) were prepared, in which the distances separating the ester functions from each other and from the carboxamide function of thep‐aminobenzoate moiety were variedviathe use of methylene groups as “spacers”. The diethyl esters3and4, with D,L‐α‐aminoadipate and D,L‐α‐aminopimelate side chains in place of L‐glutamate, displayed approximately the same order of activity as compound1against bacterial and mammalian cells in culture, and were inhibitors of the enzyme dihydrofolate reductase. When given intraperitoneally to L1210 1eukemic mice at a dose of 120 mg./kg. q3d 1,4,7, compound4produced a 67% increase in survival and no evidence of toxicity, whereas methotrexate diethyl ester (1) gave a 44% increase in survival at a dose of 45 mg./kg. q3d 1,4,7 but was toxic at higher doses. The positional is

ISSN:0022-152X    

DOI:10.1002/jhet.5570130408

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractThe separation and characterization of the six possible isomers of 2,3,5,6‐tetramethylmorpholine are described. Synthetic routes for the preparation of any isomer in fair yield from easily accessible intermediates are reporte

ISSN:0022-152X    

DOI:10.1002/jhet.5570130409

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY

摘要:

AbstractPh(C2)CH2Cl and Ph(C2)'CO2Na [where (C2) = ‐C=C‐ ortrans‐CH=CH‐, (C2)' = ‐C=C‐ orcis‐CH=CH‐] reacted in refluxing dimethylformamide to yield unsaturated esters Ph(C2)'CO2‐CH2(C2)Ph and/or their intramolecular Diels‐Alder cyclization products (cyclolignan lactones). It was found that modal selectivity for cyclization in DMF sometimes varies from that found previously with acetic anhydride as solvent. Two new parent tetrahydrocyclolignan lacton

ISSN:0022-152X    

DOI:10.1002/jhet.5570130410

出版商:Wiley‐Blackwell    

年代:1976

数据来源: WILEY