摘要:

AbstractThe ketone C18H32O, obtained by the oxidation of vitamin‐D3and which still contains the rings C and D of the original sterol, appears to be readily converted into an isomer and the same holds for its semicarbazone. This isomerisation is to be explained by the conversion of the trans‐hydrindane into the cis‐hydrindane configuration. From this it is concluded that the junction between the rings C and D in vitamin‐D3, 7‐dehydrocholesterol and cholesterol very probably has the trans‐co

ISSN:0165-0513    

DOI:10.1002/recl.19480670502

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

Abstract2‐Aminofluorene condenses with pyruvic acid to yield the cinchoninic acid, 6‐methyl‐2,3‐(fluoreno)2′,1′‐pyridine‐4‐carboxylic acid. The compound is readily decarboxylated to 6‐methyl‐2,3‐(fluoreno‐2′1′)‐pyridine]. The possible significance of the cinchoninic acid structure for chemi

ISSN:0165-0513    

DOI:10.1002/recl.19480670503

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

Abstract2‐Aminofluorene reacts with dihydroxymalonic ester yielding ethyl fluorene dioxindole carboxylate, which is readily hydrolysed and oxidised to an isatin derivative, 2′,3′‐indeno‐4,5‐isatin. The latter compound yiel

ISSN:0165-0513    

DOI:10.1002/recl.19480670504

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

AbstractThe solubilities of the carcinogenic amines, 2‐naphthylamine, 2‐aminofluorene, 2‐anthramine, 4‐aminostilbene, 4‐aminoazobenzene and benzidine in water and in aqueous solutions of caffeine have been examined and it has been found that caffeine exerts a solubilising action on all these amines. Caffeine has quite a marked solubilising action on the simpler amine, 1‐methoxy‐2‐amino‐4‐nitrobenzene and it has been shown that sulphapyridine and sulphathiazole are more soluble in caffeine solutions than in water.The solubility of 2‐aminofluorene has been examined in aqueous solutions of various purines and the results are of the same order as those obtained byWeil‐Malherbefor the solubility of benzpyrene in solutions of the same purines. The most efficient purines are those with the greatest degree of N‐methylation.The influence of a mixture of caffeine and 1,3,7‐trimethyluric acid on the solubility of 2‐aminofluorene in water has been studied and it is shown that the solubilising power of the mixture is less than the sum of the separate effects of each purine on the solubility of the amine. This is taken to mean that the purines antagonise each other probably owing to forces acting between themselves of the same nature as those responsible for the aminofluorene‐purine solubility effects. This effect, which requires further study would probably be of importance in biological systems.Some evidence is given that 2‐phenyl‐quinoline‐4‐carboxylic acid (cinchophen) is solub

ISSN:0165-0513    

DOI:10.1002/recl.19480670505

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

Abstract6‐Methyl‐[acenaphtheno‐5′,4′‐2,3‐pyridine]‐4‐carboxylic acid has been prepared by reacting 5‐aminoacenaphthene with pyruvic acid in ethanol. The compound was decarboxylated by soda‐lime to give 6‐methyl‐[acenaph

ISSN:0165-0513    

DOI:10.1002/recl.19480670506

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

Abstract3‐Acetylamino‐5‐ethoxypyridine was prepared by converting 3,5‐dibromopyridine with sodium ethylate into 3‐bromo‐5‐ethoxypyridine, allowing this substance to interact with ammonia and acetylating the aminoethoxypyridine thus formed with ace

ISSN:0165-0513    

DOI:10.1002/recl.19480670507

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

AbstractCrouchandLochtehave described a new synthesis of pyridine derivatives, in which they start from glutarimide or from its alkyl derivativesW. W. CrouchandH. L. Lochte, J. Am. Chem. Soc.65, 270 (1943).). By the action of phosphorus pentachloride on glutarimide at a slightly raised temperature they obtained a trichloropyridine, m.p. 66‐67° and they have shown indirectly that this compound is the 2,3,6‐isomer.We have now reacted glutarimide with phosphorus pentabromide and have confirmed the reasoning ofCrouchandLochte, because the tribromopyridine obtained has been identified with 2,3,6‐tribromopyridine, prepared by brominating 3‐bromopyridine at 500°H. J. den HertogandJ. P. Wibaut, Rec. trav. chim.51, 940 (1932).. Moreover, 2,3,5,6‐tetra‐bromopyridine appeared to be formed, which was identified with a sample obtained by brominating 3,5‐dibromopyridine at 500°.Glutarimide (1 g) was mixed with phosphorus pentabromide (12 g) and the mixture held at 80‐90° for 2 1/2 hours. The reaction product was then poured out into water and the crystals, which separated after a little time, were submitted to a steam distillation. The first fraction in the steam distillation (60 cm3) contained a colourless solid, which melted at 82.5‐83.5° after crystallisation from ethanol. (Mixed m.p. with a sample of 2,3,6‐tribromopyridine: 82‐83°.) After an intermediate fraction of 50 cm3had passed over in the steam distillation, a further fraction was obtained (250 cm3), which contained a colourless substance melting at 103‐104° after crystallisation from ethanol. (Mixed m.p. with a sample of 2,3,5,6

ISSN:0165-0513    

DOI:10.1002/recl.19480670508

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

AbstractThe action of sodium methylate on 2,4,6‐tribromopyridine is described. The bromine atoms are very easily replaced by methoxyl groups, in the order 4, 2, 6. A proof of structure is given for each of the substances forme

ISSN:0165-0513    

DOI:10.1002/recl.19480670509

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

AbstractThe action of sodium phenate on 2,4,6‐tribromopyridine has been investigated. The order in which the bromine atoms are replaced appeared to be dependent on the solvent used. In phenol the bromine atoms in positions 2 and 6 reacted first and then that in position 4; in water the rate of replacement of the 4 bromine atom had relatively increased, becoming even greater than that of the atoms in positions 2 and 6.The structure of the substances formed was proved by converting them into phenoxypyridines, the constitution of which was established by synthesis from mono‐ and dibromopyridi

ISSN:0165-0513    

DOI:10.1002/recl.19480670510

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY

摘要:

AbstractThe melting point diagram of the system sulphur‐anthracene has been determined. It is characterized by an inflection point in the anthracene branch with a rather small inclination. No liquid immiscibility in the metastable nor in the stable region was detecte

ISSN:0165-0513    

DOI:10.1002/recl.19480670511

出版商:WILEY‐VCH Verlag    

年代:1948

数据来源: WILEY