4- Oxovaleric acid

NH3-gas passed at room temp, into a ca. 20 -soln. of 4,4-dimethyl-2-oxovaleric acid thioamide and cyclohexanone in methanol until the orange soln. turns yellow, and allowed to stand 10 min. 2,2-pentamethylene-4-neopentyl-J -imidazoline-5-thione. Y 89. F. e. s. F. Asinger and F. Gentz, M. 96, 1474 (1965). 

Although these derivatives are limited to 2-oxocarboxylic acids, their mass spectra give rise to several ions which are common to most of the compounds in the series and permit their detection by SIM (Langenbeck etal., 1977a). The mass spectrum of the trimethylsilylated quinoxalinol formed from 2-oxovaleric acid is shown in Fig. 5.19. 

Fig. 5.19 Mass spectrum of the trimethylsilyl derivative of the quinoxalinol of 2-oxovaleric acid.

Kost et al. studied the interaction of indole magnesium iodide with a number of cyclic anhydrides of dibasic organic acids.In addition to 254 the following. 3-indolyloxo acids were prepared in this manner -(3-indolyl)-8-oxovaleric acid (274), y-(3-indolyl)-y-oxocrotoiiic acid... 

S-(3-indolyl)-8-oxovaleric acid (274), y-(3-indolyl)-y-oxocrotonic acid... 

Fig. 13.3 Signaling pathways involved in oxidized phospholipid-induced apoptosis in mammalian smooth muscle and endothelial cells. AIF, apoptosis inducing factor Apaf-1, apoptosis activating factor 1 aSM, acid sphingomyelinase Az-PC azelaoyl acid ester of lyso-PC Cyt c, cytochrome c G-PC, glutaric acid ester of lyso-PC IM, intermembrane space of the mitochondria JNK, c-Jun N-terminal kinase OV-PC, 5-oxovaleric acid ester of lyso-PC p38, p38 mitogen-activated protein kinase PM, plasma membrane...

Electrophilic substitution of the carbonyl compounds occurs the more easily the less the carbonyl group is stabilized by mesomerism. It is increasingly difficult in the series ketone — acid chloride — acid anhydride — ester, carboxylic acid — carboxyamide.546 This gradation can be illustrated by, for instance, the bromination of levulic acid (4-oxovaleric acid) with 2 moles... 

Oxotricyclo (5.2.1.0 ) decane. See Tricycio [5.2.1.0 T decane-8-one Oxo-tridecyl acetate. See Oxo-dodecyl acetate 4-Oxovaleric acid 4-Oxo-n-valeric acid. See Levulinic acid... 

Hydroxy-4-oxovaleric acid, see H-20213 27-Hydroxy-3-oxowitha-1,4,24-trienolide, H-10213... 

Piperidines. A soln. of 5-phenyl-5-oxovaleric acid methylamide in benzene added with effective stirring to a soln. of ca. 300% excess LiAlH4 in ether, and refluxed ca. 6 hrs. l-methylamino-5-phenyl-5-pentanol (Y 82%) neutralized with 1 iV HBr, concentrated, dried by distillation with chloroform, treated with PBrg, and the product isolated the next day l-methyl-2-phenyl-piperidine (Y 80%). F, e. s. R. Luke and M. Cerny, Coll. Czech. Ghem. Commons. 2A, 1287 (1959). 

Hydroxy-n-valeric acid is perhaps the most frequently observed urinary metabolite after methylcitrate and 3-hydroxypropionate, and 3-oxo-/r-valeric acid may also occur during severe ketosis. During non-ketotic periods, when propionyl-CoA accumulation still occurs, two molecules of this substrate may condense via the action of a j3-ketothiolase to form 2-methyl-3-oxovaleryl-CoA, resulting ultimately in the excretion of 2-methyl-3-hydroxyvaleric and 2-methyl-3-oxovaleric acids in the urine (Lehnert et ai, 1978 Truscott et al., 1979). The occurrence of these keto acids explains the presence of long-chain ketones in the urine, formed by decarboxylation in an analogous manner to the formation of acetone from acetoacetate (Fig. 11.6). 

Lehnert, W., Schuchmann, L., Urbdnek, R., Niederhoff, H. and Bohm, N. (1978), Excretion of 2-methyl-3-oxovaleric acid in propionic acidemia. Eur. J. Pediatr., 128, 197. 

A ring-chain equilibrium displaced in favor of the cyclic tautomer was observed [78JBC(253)5407 83LA1623] in neutral aqueous solutions of 5-carbamido- 66 n = 3 Xt = 5.67) and 5-guanidino-2-oxovaleric 67 n = 3 Xt = 3.17) acids. In aqueous solutions of acid 67 (w = 3), H-NMR spectroscopy detected the presence of 4% of the open-chain tautomer hydrate 67A (n = 3). In acidic medium, the amount of this hydrate is higher. The dipolar cyclic structure of 67B (n = 3) in the solid state was established on the basis of X-ray diffraction data [83AX(C)1240]. Both isomers 67A and... 

In 1941 Gakhokidze40 realized a different type of Grignard synthesis on a carbohydrate acid derivative. Methyl L-ery(liro-3,4,5-trimethoxy-2-oxovalerate (XXXII), was treated with one mole of methylmagnesium iodide to produce methyl 2-methyl-2-hydroxy-L-er /(firo-3,4,5-trimethoxy-valerate (XXXIII). The configuration of the second carbon atom in... 

SYNS ETHYLKETOVALERATE ETHYL 4-KETOVALERATE ETHYL LAEVULINATE ETHYL LEVULATE ETHYL 4-OXOPENTANOATE ETHYL 4-OXOVALERATE LEVULINIC ACID, ETHYL ESTER... 

C6H10O2 cis-3-methyl-2-pentenoic acid 19866-51-4 475.00 41.487 2 7908 C6H10O3 methyl 3-oxovalerate 30414-53-0 459.55 40.012 2... 

C8H1402 1-methyl-1-cyclohexanecarboxylic acid 1123-26-7 507,15 44.572 1,2 14724 C8H1405 methyl 4,4-dimethoxy-3-oxovalerate 62759-83-5 473.15 2... 

The reaction, under the same conditions, has been extended to other /3-keto esters. Ethyl 3-oxovalerate, ethyl 3-oxohexanoate, and diethyl 3-oxoglutarate react with 2-amino-2-deoxy-D-glucose to give compounds (11), (12), and (13), respectively, whose oxidations with lead tetraacetate or periodic acid furnish the corresponding aldehydes (14), (IS), and (16). 

An unexpected transformation, the exclusive formation of ethyl 2,2,4-trimethyl-3-oxovalerate, taking place via ring scission with the participation of solvent ethanol, was observed on Ni-P foil prepared by electrolytic reduction. After preparation this foil was treated with sulfuric acid to dissolve the Cu plate used as substrate to deposit the amorphous Ni-P foil. We attribute this unusual transformation to acidic centres of the catalyst formed during the latter treatment. In an independent experiment, 1 was reacted without any catalyst in 1 M ethanolic hydrochloric acid at 398 K. The ring-opened ketoester was the only product formed, indicating that the transformation is an acid-catalysed process. The mechanism proposed to account for the selective ring-opening is to be seen in Fig. 2. 

A soluble alanine aminotransferase considerably purified from tomato fruit tissue (Rech and Crouzet, 1974) did not use aspartate, glycine, threonine, leucine, methionine, arginine, or phenylalanine as amino donors glyoxylate and 2-oxovalerate were not used as amino acceptors. Mitochondria from tomato fruit yielded what was apparently the same protein (Gazeu-Reyjal and Crouzet, 1976). The mitochondrial enzyme did not utilize threonine, methionine, aromatic or branched-chain amino acids. 

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