Guang-Zhong Wu - Somerville NJ Xing Chen - Plainsboro NJ Doris P. Schumacher - Bedminster NJ Martin Steinman - Livingston NJ
Assignee:
Schering Corporation - Kenilworth NJ
International Classification:
C07D20508
US Classification:
540200
Abstract:
The invention relates to a process for producing a compound of the formula ##STR1## wherein R. sub. 1, R. sub. 2 and R. sub. 3 are as defined in the specification, which comprises the steps of: (a) reacting a lactone with an imine to obtain a chiral diol of the formula IV; (b) oxidizing the diol to obtain an aldehyde of formula V; (c) condensing the aldehyde with an enolether followed by dehydration to obtain a compound of formula VI; (d) hydrogenating the compound of formula VI to obtain a ketone of formula VII; and (e) chirally catalytically reducing the ketone, wherein steps (b)-(d) are shown in the following reaction scheme: ##STR2##.
3-Hydroxy Gamma-Lactone Based Enantioselective Synthesis Of Azetidinones
George G. Wu - Basking Ridge NJ Xing Chen - Plainsboro NJ Doris P. Schumacher - Bedminster NJ Martin Steinman - Livingston NJ
Assignee:
Schering Corporation - Kenilworth NJ
International Classification:
C07D20508
US Classification:
540200
Abstract:
The invention relates to intermediates of the formulae ##STR1## said intermediates being useful in a process for producing a compound of the formula ##STR2## wherein Bn is benzyl and R. sub. 1,. sub. 2 and R. sub. 3 are as defined in the specification,.
3-Hydroxy .Gamma.-Lactone Based Enantionselective Synthesis Of Azetidinones
Guang-Zhong Wu - Somerville NJ Xing Chen - Plainsboro NJ Doris P. Schumacher - Bedminster NJ Martin Steinman - Livingston NJ
Assignee:
Schering Corporation - Kenilworth NJ
International Classification:
C07D20504
US Classification:
540200
Abstract:
The invention relates to a process for producing the compound of the formula ##STR1## which comprises reacting lactone of formula II ##STR2## with an imine of formula III': ##STR3## and converting the resulting chiral diol of formula VI: ##STR4## through several steps to obtain a compound of formula I'.
Synthesis Of Intermediates Useful In Preparing Tricyclic Compounds
Xing Chen - Plainsboro NJ Marc Poirier - Parlin NJ Guang-Zhong Wu - Neshanic Station NJ
Assignee:
Schering Corporation - Kenilworth NJ
International Classification:
C07D22106
US Classification:
546 93
Abstract:
The invention relates to a process for preparing a compound of the formula ##STR1## comprising reacting a bromo-substituted pyridine with an amine of the formula NHR. sup. 5 R. sup. 6, reacting the resulting amide with an iodo-halomethyl-substituted compound and cyclizing the resultant product, wherein R, R. sup. 1, R. sup. 2, R. sup. 3 and R. sup. 4 are as defined in the specification; also claimed are a compound of the formula ##STR2## and a process for preparing it from the corresponding halo-substituted benzoic acid.
Synthesis Of Intermediates Useful In Preparing Bromo-Substituted Tricyclic Compounds
The invention relates to a process for preparing a compound of the formula ##STR1## comprising: (a) reacting 2,5-dibromo-3-methylpyridine with an amine of the formula NHR. sup. 5 R. sup. 6 to obtain an amide; (b) reacting the amide with a compound of formula 3 ##STR2## in the presence of a strong base to obtain a compound of formula 4 ##STR3## (c) converting a compound of formula 4 to the corresponding cyano compound or aldehyde; (d) reacting the cyano compound or aldehyde with a piperidine derivative to obtain an aldehyde or alcohol of formula 7a or 7b, respectively: ##STR4## (e) cyclizing a compound of formula 7a or 7b; wherein R. sup. 1 -R. sup. 7 are as defined in the specification.