Patents by Inventor Nhan H. Nguyen

Nhan H. Nguyen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5763357
    Abstract: Herbicidal 3-substituted pyridine compounds and derivatives thereof of the formula: ##STR1## wherein Ar is a substituted or unsubstituted 5- or 6-membered heteroaryl group having 1, 2 or 3 ring nitrogen atoms with the remainder of the ring atoms being carbon; a substituted or unsubstituted 5-membered heteroaryl group having a ring heteroatom of oxygen or sulfur with the remainder of the ring atoms being carbon; or a substituted or unsubstituted 5-membered heteroaryl group having one ring nitrogen atom and either an oxygen or sulfur ring heteroatom with the remainder of the ring atoms being carbon. Herbicidal compositions containing such 3-substituted pyridine compounds and derivatives thereof and methods of controlling undesirable vegetation employing these compounds and derivatives are also disclosed. The compounds in which XR is hydroxyl are also useful as intermediates for producing the disclosed 3-substituted pyridine derivatives.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: June 9, 1998
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling M. Chin, Nhan H. Nguyen, David B. Kanne, David L. Lee
  • Patent number: 5672567
    Abstract: Herbicidal substituted hydroxybenzyl-heteroaryl compounds and derivatives thereof of the formula ##STR1## wherein Ar is a substituted or unsubstituted 5- or 6-membered heteroaryl group having 2 or 3 ring nitrogen atoms or a substituted or unsubstituted 5-membered heteroaryl group having two ring heteroatoms, one of the ring heteroatoms being nitrogen and the other being sulfur or oxygen. Herbicidal compositions containing such substituted hydroxybenzyl-heteroaryl compounds and derivatives thereof and methods of controlling undesirable vegetation employing these compounds and derivatives are also disclosed. The compounds in which XR is hydroxyl are also useful as intermediates for producing the disclosed substituted hydroxybenzyl-heteroaryl derivatives.
    Type: Grant
    Filed: March 25, 1996
    Date of Patent: September 30, 1997
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling M. Chin, Yi-Qiu Wei, Nhan H. Nguyen, David B. Kanne
  • Patent number: 5670453
    Abstract: Herbicidal substituted hydroxybenzyl-heteroaryl compounds and derivatives thereof of the formula ##STR1## wherein Ar is a substituted or unsubstituted 5- or 6-membered heteroaryl group having 2 or 3 ring nitrogen atoms or a substituted or unsubstituted 5-membered heteroaryl group having two ring heteroatoms, one of the ring heteroatoms being nitrogen and the other being sulfur or oxygen. Herbicidal compositions containing such substituted hydroxybenzyl-heteroaryl compounds and derivatives thereof and methods of controlling undesirable vegetation employing these compounds and derivatives are also disclosed. The compounds in which XR is hydroxyl are also useful as intermediates for producing the disclosed substituted hydroxybenzyl-heteroaryl derivatives.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: September 23, 1997
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling M. Chin, Yi-Qiu Wei, Nhan H. Nguyen, David B. Kanne
  • Patent number: 5595958
    Abstract: Herbicidal 3-substituted pyridine compounds and derivatives thereof of the formula: ##STR1## wherein Ar is a substituted or unsubstituted 5- or 6-membered heteroaryl group having 1, 2 or 3 ring nitrogen atoms with the remainder of the ring atoms being carbon; a substituted or unsubstituted 5-membered heteroaryl group having a ring heteroatom of oxygen or sulfur with the remainder of the ring atoms being carbon; or a substituted or unsubstituted 5-membered heteroaryl group having one ring nitrogen atom and either an oxygen or sulfur ring heteroatom with the remainder of the ring atoms being carbon. Herbicidal compositions containing such 3-substituted pyridine compounds and derivatives thereof and methods of controlling undesirable vegetation employing these compounds and derivatives are also disclosed. The compounds in which XR is hydroxyl are also useful as intermediates for producing the disclosed 3-substituted pyridine derivatives.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: January 21, 1997
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling M. Chin, Nhan H. Nguyen, David B. Kanne, David L. Lee
  • Patent number: 5585327
    Abstract: 4-substituted pyridyl-3-carbinols of the formula ##STR1## wherein R is hydrogen, or an acyl, alkyl or carbamyl group exhibit desirable preemergent and postemergent herbicidal activity. Also disclosed are herbicidal compositions comprising such compounds and methods of controlling undesirable vegetation employing such compounds. The compounds wherein AR is hydroxyl serve as useful intermediates for the production of the alpha-benzyl substituted compounds as well as exhibiting herbicidal activity.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: December 17, 1996
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling Chin, Yi-Qiu Wei, Nhan H. Nguyen, Michael P. Ensminger, Linda Willitts, Derek P. Dagarin
  • Patent number: 5329041
    Abstract: 2-methyl-3-(substituted)-4-(substituted) benzoic acids or their alkyl ester that are useful to prepare herbicidal compounds.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: July 12, 1994
    Assignee: Imperial Chemical Industries PLC
    Inventor: Nhan H. Nguyen
  • Patent number: 5308826
    Abstract: 4-substituted pyridyl-3-carbinols of the formula ##STR1## wherein R is hydrogen, or an acyl, alkyl or carbamyl group exhibit desirable preemergent and postemergent herbicidal activity. Also disclosed are herbicidal compositions comprising such compounds and; a method of controlling undesirable vegetation employing such compounds. The compounds wherein AR is hydroxyl serve as useful intermediates for the production of the alpha-benzyl substituted compounds as well as exhibiting herbicidal activity.
    Type: Grant
    Filed: April 22, 1993
    Date of Patent: May 3, 1994
    Assignee: Zeneca Limited
    Inventors: Hsiao-Ling M. Chin, Yi Q. Wei, Nhan H. Nguyen
  • Patent number: 5110979
    Abstract: 2-methyl-3-(substituted)-4-(substituted) benzoic acids or their alkyl ester that are useful to prepare herbicidal compounds.
    Type: Grant
    Filed: January 15, 1991
    Date of Patent: May 5, 1992
    Assignee: Imperial Chemical Industries PLC
    Inventor: Nhan H. Nguyen
  • Patent number: 5092919
    Abstract: Herbicidal compounds of the structural formula ##STR1## wherein R.sup.1 is hydrogen or C.sub.1 -C.sub.4 alkyl; R.sup.2 is hydrogen or C.sub.1 -C.sub.4 alkyl; R.sup.3 is hydrogen or C.sub.1 -C.sub.4 alkyl; R.sub.4 is hydroxy, hydrogen or C.sub.1 -C.sub.4 alkyl; or R.sup.3 and R.sup.4 together are carbonyl (.dbd.O) with the proviso that R.sup.1, R.sup.2, R.sup.5 and R.sup.6 are C.sub.1 -C.sub.4 alkyl; R.sup.5 is hydrogen or C.sub.1 -C.sub.4 alkyl; R.sup.6 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkylthio, or C.sub.1 -C.sub.4 alkylsulfonyl, with the proviso that when R.sup.6 is C.sub.1 -C.sub.4 alkylthio or C.sub.1 -C.sub.4 alkylsulfonyl, the R.sub.3 and R.sup.4 are not together carbonyl; R.sup.7 is methyl or ethyl; and R.sup.8 is (1) halogen; (2) nitro; or (3) R.sup.b SO.sub.n -- wherein n is the integer 0 or 2, and R.sup.b is (a) C.sub.1 -C.sub.4 alkyl; and its salts.
    Type: Grant
    Filed: January 15, 1991
    Date of Patent: March 3, 1992
    Assignee: Imperial Chemical Industries plc
    Inventor: Nhan H. Nguyen
  • Patent number: 4997473
    Abstract: Compunds of the formula ##STR1## wherein R is halogen, C.sub.1 -C.sub.2 alkyl, nitro, C.sub.1 C.sub.2 haloalkyl, C.sub.1 -C.sub.2 alkoxy, C.sub.1 -C.sub.2 alkylthio or C.sub.1 C.sub.2 alkylsulfonyl; R.sup.1 is hydrogen or C.sub.1 -C.sub.2 alkyl; R.sup.2 is hydrogen or C.sub.1 -C.sub.2 alkyl; R.sup.3 is hydrogen or C.sub.1 -C.sub.2 alkyl; and R.sup.4 and R.sup.5 independently are (1) hydrogen; (2) halogen; (3) C.sub.1 -C.sub.4 alkyl; (4) C.sub.1 -C.sub.4 alkoxy; (5) trifluoromethoxy; (6) cyano; (7) nitro; (8) C.sub.1 -C.sub.4 haloalkyl; (9) R.sup.b SO.sub.n - wherein n is the integer 0, 1 or 2; and R.sup.b is (a) C.sub.1 -C.sub.4 alkyl, (b) C.sub.1 -C.sub.4 alkyl substituted with halogen or cyano; (c) phenyl; or (d) benzyl; (10) --NR.sup.c R.sup.d wherein R.sup.c and R.sup.d independently are hydrogen or C.sub.1 -C.sub.4 alkyl; (11) R.sup.3 C(O)- wherein R.sup.3 is C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy; or (12) --SO.sub.2 NR.sup.c R.sup.d wherein R.sup.c and R.sup.d are as defined; and (13) --N(R.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: March 5, 1991
    Assignee: ICI Americas Inc.
    Inventor: Nhan H. Nguyen
  • Patent number: 4925965
    Abstract: Compounds of the formula ##STR1## wherein R is hydrogen; halogen; C.sub.1 -C.sub.2 alkyl; C.sub.1 -C.sub.2 alkoxy; nitro; cyano; C.sub.1 -C.sub.2 haloalkyl; or R.sup.a SO.sub.n -- wherein n is 0 or 2 and R.sup.a is C.sub.1 -C.sub.2 alkyl, trifluoromethyl or difluoromethyl; or trifluoromethoxy or difluoromethoxy;R.sup.1 is hydrogen or C.sub.1 -C.sub.4 alkyl;R.sup.2 is hydrogen or C.sub.1 -C.sub.4 alkyl; orR.sup.1 and R.sup.2 together are C.sub.2 -C.sub.5 alkylene;R.sup.3 is C.sub.1 -C.sub.4 alkyl;R.sup.4 is C.sub.1 -C.sub.4 alkyl; orR.sup.3 and R.sup.4 together are C.sub.2 -C.sub.5 alkylene;R.sup.5 and R.sup.6 independently are (1) hydrogen; (2) halogen; (3) C.sub.1 -C.sub.4 alkyl; (4) C.sub.1 -C.sub.4 alkoxy; (5) trifluoromethoxy; (6) cyano; (7) nitro; (8) C.sub.1 -C.sub.4 haloalkyl; (9) R.sup.b SO.sub.n -- wherein n is the integer 0, 1 or 2; and R.sup.b is (a) C.sub.1 -C.sub.4 alkyl; (b) C.sub.1 -C.sub.4 alkyl substituted with halogen or cyano; (c) phenyl; or (d) benzyl; (10) --NR.sup.c R.sup.d wherein R.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: May 15, 1990
    Assignee: ICI Americas Inc.
    Inventor: Nhan H. Nguyen