3057-04-3Relevant articles and documents
CO2 incubator ozone sterilization device
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, (2007/10/16)
PROBLEM TO BE SOLVED: To provide an apparatus that ensures sterilization of a COincubator, has no leakage of fed ozone gas to the outside, uniformly circulates ozone in a storage and constantly and continuously controls an ozone concentration.SOLUTION: The apparatus for ozone sterilization of a COincubator includes: a sterilization tent 1 with an airtight hole 8a for airtightly protruding a leading end part of a tube connection part 14a provided in the COincubator 11 to the outside and a discharge part 9a for discharging ozone gas to the outside, for covering the COincubator 11 airtightly; an ozone gas generator 18 for applying circulating sterilization to the inside and the outside of the COincubator 11 covered by the sterilization tent 1 by pressure-feeding the ozone gas to the tube connection part 14a; and an ozone gas neutralization unit 26 for neutralizing and eliminating the ozone gas discharged from the discharge part 9a.
Efficient lipase-catalyzed preparation of long-chain fatty acid esters of bile acids: Biological activity and synthetic application of the products
Sugai, Takeshi,Takizawa, Masahiro,Bakke, Mikio,Ohtsuka, Yoshikazu,Ohta, Hiromichi
, p. 2059 - 2063 (2007/10/03)
A highly regioselective (3-position) and efficient (quantitative yield) acylation of bile acids catalyzed by immobilized Candida antarctica lipase was established. Methyl cholate derivatives acylated with long-chain fatty acids (C12-C16) showed an inhibitory effect on the growth of some strains of Gram-positive and -negative bacteria (27-400 μg/ml). The anti-bacterial activity was slightly weaker than has been observed for methyl cholate, while the increased lipophilicity and lower melting points of the present derivatives are well suited for a potential germicide which would be safe and be topically applied. This enzyme-catalyzed transesterification is also demonstrated as an expeditious route to ursodeoxycholic acid, in respect of the regioselective introduction of acyl protecting groups on the hydroxyl groups of the intermediates. 7-Ketolithocholic acid, a known direct precursor of ursodeoxycholic acid, was obtained from cholic acid via chenodeoxycholic acid in a 46% yield and 9 steps.
BILE ACIDS LXIX. SELECTIVE K-SELECTRIDE REDUCTION OF 3,7-DIKETO STEROIDS
Tal, Daniel M.,Frisch, G. Douglas,Elliott, William H.
, p. 851 - 854 (2007/10/02)
The K-Selectride reduction at low temperature (-45 C) of 7-oxo-5α-cholestan-3β-yl acetate and methyl 7-oxo-3α-hydroxy-5β-cholanoate resulted in almost quantitative yield of the 7α-alcohol in the 5α-compound but only moderate yield of the 5β-analog.The simultaneous reduction of two carbonyl in the 3 and 7 positions afforded good to excellent yields of the diaxial diol in planar steroids (methyl 3,7-dioxo-5α-cholanoate, 3,7-dioxo-5α-cholestane and methyl 3,7-dioxo-5α-cholestan-27-oate) and only 14percent of 3α,7α-(OH)2 from methyl 3,7-dioxo-5β-cholanoate.