Gamma lactones

Nitz, S., Kollmannsberger, H., Drawer F. (1989) Determination of non natural flavours in sparkling fruit wines. I Rapid method for the resolution of enantiomeric gamma lactones by multidimensional GC. Chem. Mikrobiol. Techno Lebensm. 12 75-80. 

Nishikimi, M., Fukuyama, R., Minoshima, S., Shimizu, N., and Yagi, K., 1994, Cloning and chromosomal mapping of the human nonfunctional gene for L-gulono-gamma-lactone oxidase, the enzyme for L-ascorbic acid biosynthesis missing in man. J. Biol. Chem. 269 13685-13688. 

Augustyn, O.P.H., Van Wyk, C.J., Muller, C.J., Kepner, R.E., Webb, A.D. (1971). The structure of solerone (5-acetyldihydro-2-(3H)furanone) a substituted gamma-lactone involved in wine aroma. J. Agric. Food Chem, 19, 1128-1130. 

Wurz, R. E. M., Kepner, R. E., Webb, A. D. (1988) The biosynthesis of certain gamma-lactones from glutamic acid by film yeast activity on the surface of Flor Sherry. American Journal of... 

Aqueous solutions of gluconic add are equilibrium mixtures of uconic add itself, togetiier with tiie gamma and delta lactones. Hie relative concentrations of each of these can be profoundly influenced by the temperature at which crystals are allowed to separate out, a situation aided by seeding with the appropriate required crystal. At temperatures below 30°C, and particularly between 0 to 4°C, free gluconic add predominates. Between 30 and 75°C tiie predominant crystals are mainly ddta lactone and above 70°C the prindpal crystals are tiie gamma lactone. 

The directions of the optical rotations of the lactones (presumably gamma lactones) and phenylhydrazides of the four 3-deoxypentonic acids are in agreement with those predicted, on the basis of the assigned configurations, by the lactone and phenylhydrazide rules. 

The taste of ripe peaches is dominated by the sweet succulent juice with its very aromatic fmity and fresh aroma. The heavy fruity, fatty, typical peachy note, also found in plums, nectarines, apricots is called lactony , and it is derived from gamma-lactones. 

Gamma-lactones are quite prevalent in biolipids and in microbiological transformation products. Any of these may be the source of y-lactones. Hydroxy-acids and unsaturated acids may also be the source of y-lactones in Aleksinac shale. If y-lactones were found to be typical for certain class of sediments, they might shed more light on the source of the organic matter of these sediments. 

Fishbein, W.N. and Bessman, S.P. (1966). Purification and properties of an enzyme in human blood and rat liver microsomes catalyzing the formation and hydrolysis of gamma-lactones. J. Biol. Chem. 241 4835-4841. 

Biggadike, H.G. et al. Selective plasma hydrolysis of glucocorticoid gamma-lactones and cyclic carbonates by the enzyme paraoxonase an ideal plasma inactivation mechanism, J. Med. Chem., 43, 19, 2000. 

Guichard E., Kustermann A. and Mosandl A. (1990) Chiral flavour compounds from apricots. Distribution of gamma-lactone enantiomers and stereodifferentiation of dihydroactinidolide using multi-dimensional gas chromatography. J. Chromatogr. 498, 396-401. 

The absolute stereochemistry of precorrin-3B was deduced by NMR and revealed that the lactone is on the upper face, cis to the C20 hydroxyl, and the C20 methyl is on the lower face. Mechanistically, it has been suggested that CobG may contain a nonheme iron, as well as an Fe4-S4 center, which could form an Fe -0 species, resulting in the insertion of a hydroxyl group followed by gamma lactone formation from the upper face of the imine (Figure 21). " Confirmation of such a mechanism awaits further characterization of CobG. 

Figure 21 Mechanism for the synthesis of precorrin-3B from precorrin-3A. In nature there are at least two distinct enzymes that can catalyze the synthesis of the hydroxyl gamma lactone derivative of precorrin-3A. In Pseudomona denitrificans this reaction is catalyzed by CobG, which likely utilizes a bound nonheme iron to activate molecular oxygen. In R. capsulatus, this reaction is mediated by CobZ, which harnesses the oxygen-binding ability of a flavin.

Studies directed at a synthesis of the morphine alkaloids. Regiocontrol in Robinson-type annulations of 2-(hydroxymethyl)-4-oxo-3-piperidinecarboxylic acid. gamma.-lactones Schultz, Arthur G. Shannon, Paul J. 

Araboascorbic acid, monosodium salt, D- CCRIS 2517 EINECS 228-973-9 Eribate Hex-2-enonic acid gamma-lactone, D-erythro-, monosodium sait D-erythro-Hex-2-enonic acid, y-lactone, monosodium salt HSDB 741 Isoascorbic acid sodium salt Isona Mercate 20 Neo-cebitate Sodium isoascorbate. Antioxidant and antimicrobial agent used in meat, poultry, and seafood industries. Crystals mp = 168-170° [al = 95° (c = 10 H2O) very soluble in H2O 916 g/100 ml). Lancaster Synthesis Co. PMP Fermentation Prods. Rhdne-Poulenc Food Ingredients. 

Gamma lactone formation by a 5-exo-trig reaction (favored)... 

Labows, J.N., McGinley, K., Webster, G. Leyden, J.J. 1979. Characteristic gamma-lactone production of the genus Pityrosporum. Appl. Environ. Microbiol., 38, 412-415. 

Yu Michael, C. Polyarylate Formation by Ester Interchange Reaction Using-Gamma Lactones as Diluent US Patent 4533720. 

Corey gamma-lactone synthesis Subtractive 0.279 2.588 0.718 2 -1 Hypohypsic... 

---