23234-86-8Relevant articles and documents
Chemo-enzymatic synthesis of optically active amino acids and peptides
Chen, Shui-Tein,Wang, Kung-Tsung
, p. 301 - 311 (2007/10/03)
The industrial alkaline protease, alcalase, is stable and active in a high concentration of organic solvents and useful as a biocatalyst for (i) diastereoselective hydrolysis of peptide esters and preparation of racemization-free peptides; (ii) selective incorporation of esters of D-amino acid into peptides in t-butanol via a selective hydrolysis of esters of D,L-amino acid, followed by using the unhydrolyzed D-esters as a nucleophile in a kinetically controlled peptide bond formation; (iii) resolution of esters of amino acid in 95% t-butanol/5% water, followed by saponification of the unreacted esters to offer both enantiomers with high yield and optical purity; (iv) completely resolve amino-acid esters with high yield and optical purity via in situ racemization of the unreacted antipode catalyzed by pyridoxal 5-phosphate; (v) cryobioorganic synthesis of peptides with increased yields 15%-40% of peptide bond formation by reaction at 5 °C instead of 25-30 °C of a kinetically controlled enzymatic reaction in alcohols.
Pharmaceutical composition having an excellent absorption property
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, (2008/06/13)
A compound represented by the formula: STR1 wherein R1 is a hydrogen atom, a fluorine atom, a nitro group, a hydroxyl group or a hydroxyl group protected by an esterifying group; X is CO or SO2 ; --Y-- is a straight bond, a lower alkylene group, a substituted or unsubstituted vinylene group, or group having the formula --CH2 --O-- or --O--CH2 --; R2 is a substituted or unsubstituted phenyl or naphthyl group, or R2 --Y--CO is N-benzyloxycarbonylphenylalanyl, N-benzyloxycarbonyl-4-fluorophenylalanyl or N-(m-methoxycinnamoyl)-phenylalanyl group; or a non-toxic salt thereof is disclosed along with pharmaceutical compositions containing these compounds and methods of using these compositions to increase the rate of absorption of medicines.
Oxime carbonates
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, (2008/06/13)
Novel carbonic acid esters are disclosed which are useful in a process for introducing esterified carboxy-type protective groups on amino and/or imino groups in amino and/or imino group - containing compounds for the temporary protection of said amino and/or imino groups. Additionally, processes for preparing said esters are also disclosed.