Cheng R Chen

US Patent:

62813919, Aug 28, 2001

Filed:

Oct 27, 1999

Appl. No.:

9/427413

Inventors:

Richard D. Tillyer - Westfield NJ
Ian W. Davies - Princeton NJ
Robert D. Larsen - Bridgewater NJ
Xin Wang - Kirkland, CA
Paul O'Shea - Montreal, CA
Anthony On-Ping King - Hillsborough NJ
Dalian Zhao - Fanwood NJ
Cheng Y. Chen - Colonia NJ
Edward J. J. Grabowski - Westfield NJ

Assignee:

Merck & Co., Inc. - Rahway NJ
Merck Frosst Canada & Co. - Kirkland

International Classification:

C07C31920

US Classification:

568 43

Abstract:

This invention encompasses a novel process for synthesizing compounds represented by formula A: ##STR1## These compounds are intermediates useful in the preparation of certain agents that are selective COX-2 inhibitors.

US Patent:

59319283, Aug 3, 1999

Filed:

May 7, 1997

Appl. No.:

8/852657

Inventors:

Daniel M. Brennan - Hillsdale NJ
Cheng T. Chen - Holmdel NJ

Assignee:

3Com Corporaton - Santa Clara CA

International Classification:

G06F 1314
G06F 1320

US Classification:

710 68

Abstract:

Apparatus for an improved ISDN terminal adapter (5) and accompanying methods for use therein. The adapter provides automatic ISDN switch detection, automatic SPID configuration, baud rate unblocking and automatic data compression. Specifically, the adapter automatically provides B-channel data compression in the event the DTE is unwilling or unable to do so. Here, the adapter monitors negotiation, over an ISDN line, of a compression control protocol (CCP) between the DTE and its PPP peer (380). If the negotiations reveal that the DTE will not undertake compression, then the adapter will then automatically negotiate the protocol and thereafter, for the duration of a call, perform compression and decompression in lieu of the DTE.

US Patent:

6015926, Jan 18, 2000

Filed:

May 11, 1998

Appl. No.:

9/075476

Inventors:

Cheng Yi Chen - Colonia NJ
Lushi Tan - Edison NJ
Richard D. Tillyer - Westfield NJ

Assignee:

Merck & Co., Inc. - Rahway NJ

International Classification:

C07C21145
C07D26518

US Classification:

564442

Abstract:

An efficient method for the preparation of key intermediate, in the synthesis of (-)-6-chloro-4-cyclopropylethynyl-4-trifluoromethyl-1,4-dihydro-2H-3,1-ben zoxazin-2-one, a reverse transcriptase inhibitor is achieved using a chiral addition reaction to the 4-chloro-2-trifluoromethylketoaniline with an organozinc complex to give the desired alcohol. This instant method has broad applicability in the chiral addition to any prochiral ketone.

US Patent:

58564926, Jan 5, 1999

Filed:

Jan 5, 1998

Appl. No.:

/002853

Inventors:

Cheng Yi Chen - Colonia NJ
Feng Xu - Staten Island NY
Richard D. Tillyer - Westfield NJ
Dalian Zhao - Fanwood NJ

Assignee:

Merck & Co., Inc. - Rahway NJ

International Classification:

C07D21120
C07D20712

US Classification:

546185

Abstract:

An efficient method for the quantitative preparation and isolation of a compound of formula I ##STR1## or its enantiomer, a chiral mediator used in enantioselective synthesis.

US Patent:

61405159, Oct 31, 2000

Filed:

Sep 15, 1998

Appl. No.:

9/153403

Inventors:

Cheng Y. Chen - Colonia NJ
Lushi Tan - Edison NJ
Robert D. Larsen - Bridgewater NJ

Assignee:

Merck & Co., Inc. - Rahway NJ

International Classification:

C07D30712
C07D30726
C07D40112
C07D40512
C07C31500

US Classification:

549324

Abstract:

Described is a process of preparing 3-aryl, 4-aryloxy furan-5-ones which are useful as inhibitors of cyclooxygenase-2 (COX-2). Such compounds are useful as anti-inflammatory agents. The process is directed to an asymmetric synthesis which involves: a trisubstituted styrene derivative preparation via Horner-Wadsworth-Emmons reaction and subsequent one pot trifluoromethylation of the allylic alcohol; preparation of the. alpha. -hydroxyl ketone using Sharpless asymmetric dihydroxylation and Swern oxidation; the esterification of the. alpha. -hydroxyl ketone with the phenoxy acetic acid; and the Dieckman condensation of the resulting ester.

US Patent:

59525282, Sep 14, 1999

Filed:

Sep 2, 1998

Appl. No.:

9/145667

Inventors:

Cheng Yi Chen - Colonia NJ
Edward J. J. Grabowski - Westfield NJ
Paul J. Reider - Westfield NJ
Lushi Tan - Edison NJ
Richard D. Tillyer - Cranford NJ

Assignee:

Merck & Co., Inc. - Rahway NJ

International Classification:

C07C20988

US Classification:

564425

Abstract:

A process for enhancing the purity of 2R-�1-hydroxy-1-trifluoromethyl-3-cyclopropylpropyn-2-yl!-4-chloroaniline comprising the formation of an acid addition salt which is capable of rejecting the racemate in the selected organic solvent.

US Patent:

55678246, Oct 22, 1996

Filed:

May 24, 1994

Appl. No.:

8/248288

Inventors:

Cheng Y. Chen - Colonia NJ
Robert D. Larsen - Bridgewater NJ
Thomas R. Verhoeven - Cranford NJ

Assignee:

Merck & Co., Inc. - Rahway NJ

International Classification:

C07D40112

US Classification:

548252

Abstract:

A new process is described for the synthesis of the triazolyl tryptamine: ##STR1## and related compounds. The process involves a palladium-catalyzed ring closure between a substituted ortho-iodoaniline and a protected 1-alkynol. The process is carded out at high temperature, e. g. 100. degree. C. , in a dry inert solvent, e. g. , DMF and in the presence of a proton acceptor, e. g. , Na. sub. 2 CO. sub. 3 or a trialkylamine. The triazolyl tryptamine, as well as acid addition salts thereof, is a 5 HT. sub. 1 D receptor agonist having anti-migraine properties.

US Patent:

56663625, Sep 9, 1997

Filed:

Jul 25, 1995

Appl. No.:

8/506533

Inventors:

Cheng T. Chen - Marlboro NJ
Reginald P. Best - Somerset NJ
Daniel M. Brennan - Hillsdale NJ

Assignee:

3COM Corporation - Santa Clara CA

International Classification:

H04J 322

US Classification:

370420

Abstract:

A data communication system referred to as an Asynchronous/Synchronous Converter is provided to facilitate the communications between a data terminal equipment (DTE) device using the asynchronous communication port, and a dial-up router located in a digital network. When running a dial-up TCP/IP program over the asynchronous port, DTEs use a protocol called Asynchronous Point-to-Point Protocol (Asychronous PPP). On the other hand, dial-up routers usually support Synchronous PPP. The data communication system of the invention connects the DTE to the digital network and ultimately to the dial-up router and provides two way conversion between Asynchronous PPP and Synchronous PPP that is transparent to both the DTE and the router. This two way conversion is enabled in part by the converter intercepting and storing certain link control protocol (LCP) packets and using data in those packets to effect a translation.