Xing C Chen

US Patent:

58861718, Mar 23, 1999

Filed:

May 28, 1997

Appl. No.:

8/864529

Inventors:

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##.

US Patent:

60968834, Aug 1, 2000

Filed:

Dec 14, 1998

Appl. No.:

9/210921

Inventors:

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,.

US Patent:

57393214, Apr 14, 1998

Filed:

May 31, 1996

Appl. No.:

8/655785

Inventors:

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'.

US Patent:

59986204, Dec 7, 1999

Filed:

Mar 23, 1998

Appl. No.:

9/045803

Inventors:

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.

US Patent:

57602328, Jun 2, 1998

Filed:

Jun 16, 1997

Appl. No.:

8/882753

Inventors:

Xing Chen - Plainsboro NJ
Marc Poirier - Parlin NJ
Guang-Zhong Wu - Somerville NJ

Assignee:

Schering Corporation - Kenilworth NJ

International Classification:

C07D22116

US Classification:

546 93

Abstract:

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.