摘要:
A two-step process for the conversion of a trans-1-amino-2-hydroxycycloalkane stereoselectively to a cis-1-amino-2-hydroxycycloalkane is disclosed. The novel step, a one-step hydrolysis with formal inversion, can be used to convert an amide of a trans-1-amino-2-hydroxycycloalkane to a cis-1-amino-2-hydroxycycloalkane. Methods for obtaining the trans-1-amino-2-hydroxycycloalkanes and their amides from alkenes are also disclosed, as are the novel, substantially optically pure 1-amino-2-indanols and 1-amido-2-indanols obtained thereby. A preferred process converts indene to cis-1-amino-2-indanol.
摘要:
A method for the enantioselective reduction of prochiral ketones using catalytic amounts of tetrahydroindeno[1,2-d][1,3,2] oxazaboroles of formula II is disclosed. ##STR1## The oxazaboroles can be generated in situ from the corresponding cis-1-amino-2-indanols or imino indanols (III) ##STR2## Novel compounds of formulas II and III are also disclosed.
摘要:
A method for the enantioselective reduction of an .alpha.-iminoketone to an .alpha.-aminoalcohol is disclosed. The method utilizes a borane reducing agent as the reducing agent and a chiral 1,3,2-oxazaborole as the catalyst. The method is applied to the synthesis of R-albuterol from methyl 5-acetylsalicylate in high yield and high optical purity.
摘要:
A two-step process for the conversion of a trans-1-amino-2-hydroxycycloalkane stereoselectively to a cis-1-amino-2-hydroxycycloalkane is disclosed. The novel step, a one-step hydrolysis with formal inversion, can be used to convert an amide of a trans-1-amino-2-hydroxycycloalkane to a cis-1-amino-2-hydroxycycloalkane. Methods for obtaining the trans-1-amino-2-hydroxycycloalkanes and their amides from alkenes are also disclosed. Novel, optically active 1-amido-2-indanols and 1-amino-2-alkanols are also disclosed.
摘要:
The invention relates to a method for producing albuterol by the resolution of a mixture of enantiomers of methyl 5-[2-[(1,1-dimethylethyl)amino]-1-hydroxyethyl]-2-(phenylmethoxy)benzoate or .alpha.-[[(1,1-dimethylethyl)amino]methyl]-4-(phenylmethoxy)-1,3-benzenedimethanol using a chiral acid such as (+/-) di-toluoyltartaric acid or (+/-) di-benzoyltartaric acid.
摘要:
A process is disclosed in which optically active glycols are produced through an electrolytic asymmetric dihydroxylation (ADH) reaction involving olefins as substrates. The ADH reaction is mediated by a catalytically active amount of osmium tetroxide or osmium-containing precursor in a protic medium in the presence of chiral ligand. Any lower valent osmium species produced in the course of the ADH reaction is regenerated electrolytically either directly in the absence of a secondary oxidant or indirectly in the presence of a secondary oxidant that itself undergoes electrolytic regeneration.
摘要:
The invention relates to a method for producing albuterol by the resolution of a mixture of enantiomers of 5-[2-[(1,1-dimethylethyl)amino]-1-hydroxyethyl]-2-hydroxybenzoate using ditoluoyltartaric acid.
摘要:
A process for the preparation of taxol and derivatives of taxol ##STR1## is disclosed. The process involves reacting a .beta.-alkoxycarbonylamino-phenylpropionic acid with a 13-hydroxy taxane to produce an ester of the taxane at C-13; and then deprotecting the .beta.-alkoxycarbonylamino-phenylpropionic ester to produce a .beta.-amido-.alpha.-hydroxybenzenepropanoic ester of the taxane. Intermediates useful in the process are also disclosed.
摘要:
A biocatalytic method of preparing optically pure precursors of paroxetine and a method of preparing paroxetine therefrom are disclosed. A racemic trans ester precursor compound of paroxetine is first prepared. The racemic trans ester precursor compound comprises a mixture of (3S,4R) and (3R,4S) enantiomers. The (3R,4S) enantiomer is hydrolyzed biocatalytically to the corresponding (3R,4S)-trans carboxylic acid or alternatively, the (3S,4R) enantiomer is biocatalytically hydrolyzed the to (3S,4R)-trans carboxylic acid in a reaction catalyzed by a isolated enzyme or a microorganism. In the first instance, the unhydrolyzed (3S,4R) enantiomer is separated from the (3R,4S)-trans carboxylic acid, whereas in the second instance the (3S,4R)-trans carboxylic acid is separated from the unhydrolyzed (3R,4S) enantiomer. The (3S,4R) enantiomer obtained following the selective hydrolysis is reduced to form a (-)-trans-(3S,4R) primary alcohol precursor of paroxetine. Paroxetine is then formed from the (-)-trans-(3S,4R) primary alcohol precursor.
摘要:
A two-step process for the conversion of a trans-1-amino-2-hydroxycycloalkane stereoselectively to a cis-1-amino-2-hydroxycycloalkane is disclosed. The novel step, a one-step hydrolysis with formal inversion, can be used to convert an amide of a trans-1-amino-2-hydroxycycloalkane to a cis-1-amino-2-hydroxycycloalkane. Methods for obtaining the trans-1-amino-2-hydroxycycloalkanes and their amides from alkenes are also disclosed. A preferred process converts indene to cis-1-amino-2-indanol.