Structure of β-Acylacrylic Acids
IN previous publications1–5 the β-formyl-, β-acetyl- and β-pivaloyl-acrylic acids were investigated by means of their spectra in the ultra-violet and infra-red. This work has been extended to comprise the α-methyl-β-acrylic acid6,7. In regard to cis–trans isomerism and open or cyclic structure for the preparations used, the infra-red spectra (in the case of acid (5) also by means of the nuclear magnetic resonance) have confirmed the following structures : (1) β-Formylacrylic acid, m.p. 53–56° C.: cyclic, cis (2) β-Acetylacrylic acid, m.p. 122–125° C.: trans (probably with a smaller amount cis-open acid) (3) β-Pivaloylacrylic acid, m.p. 84–85° C.: cyclic, cis (4) β-Pivaloylacrylic acid, m.p. 94–95° C.: trans (5) α-Methyl-β-acetylacrylic acid, m.p. 98–101° C.: cyclic, cis
Metabolism of resorcinylic compounds by bacteria: alternative pathways for resorcinol catabolism in Pseudomonas putida
Two strains of Pseudomonas putida isolated by enrichment cultures with orcinol as the sole source of carbon were both found to grow with resorcinol. Data are presented which show that one strain (ORC) catabolizes resorcinol by a metabolic pathway, genetically and mechanistically distinct from the orcinol pathway, via hydroxyquinol and ortho oxygenative cleavage to give maleylacetate, but that the other strain (O1) yields mutants that utilize resorcinol. One mutant strain, designated O1OC, was shown to be constitutive for the enzymes of the orcinol pathway. After growth of this strain on resorcinol, two enzymes of the resorcinol pathway are also induced, namely hydroxyquinol 1,2-oxygenase and maleylacetate reductase. Thus hydroxyquniol, formed from resorcinol, undergoes both ortho and meta diol cleavage reactions with the subsequent formation of both pyruvate and maleylacetate. Evidence was not obtained for the expression of resorcinol hydroxylase in strain O1OC; the activity of orcinol hydroxylase appears to be recruited for this hydroxylation reaction. P. putida ORC, on the other hand, possesses individual hydroxylases for orcinol and resorcinol, which are specifically induced by growth on their respective substrates. The spectral changes associated with the enzymic and nonenzymic oxidation of hydroxyquinol are described. Maleylacetate was identified as the product of hydroxyquinol oxidation by partially purified extracts obtained from P. putida ORC grown with resorcinol. Its further metabolism was reduced nicotinamide adenine dinucleotide dependent.
Versuche zur Synthese von Steroiden, XIII. Diensynthesen mit α‐Methyl‐β‐Äthyl‐Acrylsäure. Notiz Über Eine 7‐Methoxy‐Methyl‐Äthyl‐Hexahydro‐Phenanthren‐Carbonsäure
Fur Synthesen nach Diels-Alder wird α-Methyl-β-athyl-acrylsaure als philodiene Komponente benutzt. Die Adduktbildung mit 2.3-Dimethyl-butadien-(1.3) gibt 1.3.4-Trimethyl-6-athyl-Δ-tetrahydro-benzoesaure. Mit 6-Methoxy-1-vinyl-3.4-dihydro-naphthalin entsteht eine 7-Methoxy-methyl-athyl-hexahydrophenanthren-carbonsaure, die nicht identisch ist mit dem von G. Anner und K. Miescher synthetisierten oestrogen wirksamen Methylather der racem. α-Monodehydro-doisynolsaure.