Synthesis of vinyl acetate-1-C14

Conclusions Vinyl acetate-1-C¹⁴ was synthesized catalytically.The authors wish to thank I. B. Vasil'ev for graciously supplying the catalyst and the poly(ethylene glycol adipate).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 1860–1861, October, 1966.     

Bacterial carotenoids, XLVI. C50-Carotenoids, 14. C50-Carotenoids from Arthrobacter glacialis.

From the psychrophilic bacterium Arthrobacter glacialis have been isolated three C50-carotenoids with molecular formulae C50H72O2: the bicyclic decaprenoxanthin (1a, 7% of total carotenoids), the aliphatic bisanhydrobacterioruberin (2a, 10%) and the monocyclic A.g. 470 (3a, 83%). Decaprenoxanthin (1) and bisanhydrobacterioruberin (2) were in all respects, including chiroptical properties, identical with known carotenoids. The constitution of the previously undescribed A.g. 470 (3a) followed from its spectral properties (electronic, 1H NMR including Eu-shift experiments and mass spectra) and derivatization to 3b and 3c. 3a suffered remarkable elimination to the tridecaene 4a (C47H64O) upon DMSO/KOMe/MeOH treatment. Judged by CD data A.g. 470 (3a) also in stereochemical respect 3a appears to be half decaprenoxanthin (1a)+half bisanhydrobacterioruberin (2a). The intensity ratios of the M-92/M-106 ions on electron impact of 3a,b,c and 4a,b are consistent with the general theory.     

Spezifisch14C-kernmarkierte Phenolderivate, 1. Mitt.: Synthese von [14C]-Guajacol

Zusammenfassung Für oxydative Abbauversuche wurden verschiedene spezifisch¹⁴C-kernmarkierte Phenolderivate benötigt. Guajacol, in verschiedenen Positionen des aromatischen Ringes markiert, wurde — teils von [1-¹⁴C]-Phenol, teils von [2-¹⁴C]-Aceton ausgehend — synthetisiert.

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Specifically¹⁴C-labelled phenol derivatives, I: Synthesis of [¹⁴C]guaiacol

Various phenol derivatives,¹⁴C-labelled in different specified positions of the aromatic ring, were required for oxidative degradation studies. Guaiacol, ring-labelled in different positions, was prepared both from [1-¹⁴C]phenol and from [2-¹⁴C]-acetone.

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Herrn Prof. Dr.M. Pailer zum 60. Geburtstag in Freundschaft gewidmet.     

Access to 14C-Ring labelled phenothiazines. Synthesis of 2-chlorophenolhiazine-5a,9-14C

Through the use of a recently reported ring expansion reaction, a new route to phenolhiazines has been developed suitable for the preparation of ring labelled derivatives. As an example, the preparation of 2-chloropheno thiazine-5a,9-¹⁴C ( 1 ) is reported. Condensation of cyclohexanone-2-¹⁴C with 2-amino-4-chlorothiophenol gave the spiro-2,3-dihydro-l, 3-benzothiazole 4 which was protected by acetylation ( 5 ). Treatment of 5 with sulfuryl chloride gave the tetrahydro-phenothiazine olefin mixture 6 and 7 which was directly converted to labelled 1 via treatment with DDQ in refluxing benzene followed by hydrolysis of the acetyl group.     

Maillard Polymers Derived from D-Glucose-1 and -6-14C,Glycine-1 and -2-14C,and C-1-, and Methyl-14C Methionine

Maillard polymers were prepared from D-glucose-1 and -6-14C, glycine-1 and -2-¹⁴C, as well as C-1 and methyl-¹⁴C methionine, and the activities of the isolated polymers measured as a function of time. In both cases, C-1 of the amino acids were incorporated at the lowest levels, with D-glucose carbon atoms at the highest levels. The data support the conclusions that carbon dioxide, produced during the Maillard reaction, arises from C-1 of the amino acids, but also suggests that other carbons of the amino acids may contribute as well.     

Purified 14C Virginiamycin

Abstract

¹⁴C virginiamycin, an antibiotic composed of two synergistic factors S and M, was required for metabolism and residue studies. ¹⁴C Factors S and M were separated from crude ¹⁴C virginiamycin and purified by semi-preparative normal phase HPLC followed by crystallization/precipitation. After chemical and radiopurity assays, the two factors were recombined in a 1:4 ratio to form purified ¹⁴C virginiamycin.     

Furanverbindungen, 14. Mitt.

Zusammenfassung Eine für die Synthese linearer Furoxanthone ohne Substituenten am Furanring geeignete Methode ist dieUllmann-Kondensation von 6-Hydroxycumaran mit verschiedenen o-Chlorbenzoesäuren mit anschließender Cyclisierung und Dehydrierung. Als Beispiele werden die Synthesen von Furo[3,2-b]-, 7-Methylfuro-[3,2-b]-und 8-Methylfuro[3,2-b]xanthon beschrieben.

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A method for the synthesis of linear furoxanthones carrying no substituent in the furan ring is achieved by theUllmann condensation of 6-hydroxycoumaran with various o-chlorobenzoic acids, followed by cyclisation and subsequent dehydrogenation. This is illustrated by the synthesis of furo[3,2-b]-, 7-methylfuro[3,2-b]-and 8-methylfuro[3,2-b]xanthones.

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Diese Veröffentlichung ist ein Teil der Dissertation, dieC. S. Angadiyavar an der Karnatak University zur Erlangung des Titels eines Ph. Dr. einreichen wird.

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10. Mitt.:Y. S. Agasimundin undS. Rajagopal, Chem. Ber.100, 383 (1967).