Patents by Inventor Piyasena Hewawasam

Piyasena Hewawasam 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).

  • Publication number: 20020045566
    Abstract: The present invention describes calcium sensitive and selective maxi-K potassium channel opener/activator compounds that function to open maxi-K channels under conditions of high intracellular calcium concentrations, and which do not significantly affect the opening of maxi-K channel proteins under conditions of low or physiologically normal intracellular calcium concentrations. Methods of assaying for and using such compounds are also provided. According to the invention, whole cell voltage patch-clamp studies newly demonstrated that the ability of opener compounds, e.g., fluoro-oxindoles and chloro-oxindoles, to open maxi-K channels was sensitive to the intracellular Ca2+ concentration ([Ca2+])i, i.e., more channels opened at more negative potentials.
    Type: Application
    Filed: October 12, 2001
    Publication date: April 18, 2002
    Inventors: Valentin K. Gribkoff, Debra J. Post-Munson, Sarita W. Yeola, Christopher G. Boissard, Piyasena Hewawasam, John E. Starrett
  • Patent number: 6297241
    Abstract: The present invention provides novel carbamate oxadiazolone derivatives having the general formula wherein R1 and R2 are as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of the large conductance calcium-activated potassium channels.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: October 2, 2001
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Xi Chen, John E. Starrett
  • Patent number: 6271249
    Abstract: Novel compounds of Formula 1 are useful to treat disorders responsive to openers of the large conductance calcium-activated potassium channels: wherein “Het” is one of a select group of heterocyclic moieties; Z is independently for each occurrence selected from O or S; Ra, Rb and Rc each are independently selected from hydrogen, halogen, OH, CF3, NO2, or provided Rc is not hydrogen; and when Ra and Rb are hydrogen, Rc may be a heterocyclic moiety selected from the group consisting of imidazol-1-yl, morpholinomethyl, N-methylimidazol-2-yl, and pyridin-2-yl; Rd and Re each are independently selected from hydrogen, halogen, CF3, NO2 or imidazol-1-yl; m, n and p each are independently selected from an integer of 0 or 1; and Rf and Rg each are independently hydrogen; C1-4 alkyl; or Rf and Rg, taken together with the nitrogen atom to which they are attached, is a heterocyclic moiety selected from the group consisting of N-methylpiperazine, morpholine, thiomorpholine,
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: August 7, 2001
    Assignee: Bristol-Myers Squibb Company
    Inventors: Jeffrey L. Romine, Scott W. Martin, Piyasena Hewawasam, Nicholas A. Meanwell, Valentin K. Gribkoff, John E. Starrett, Jr.
  • Patent number: 6184231
    Abstract: The present invention provides novel 3-substituted-4-arylquinolin-2-one derivatives having the general formula wherein R, R1, R2, R3, R4, R5, R6 and R7 are as defined herein, or a non-toxic pharmaceutically acceptable salt thereof which are modulators of the large conductance calcium-activated K+ channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: February 6, 2001
    Assignee: Bristol-Myers Squibb
    Inventors: Piyasena Hewawasam, John E. Starrett, Jr.
  • Patent number: 6162817
    Abstract: The present invention provides novel carbamate oxadiazolone derivatives having the general formula ##STR1## wherein R.sup.1 and R.sup.2 are as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of the large conductance calcium-activated potassium channels.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: December 19, 2000
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Xi Chen, John E. Starrett, Jr.
  • Patent number: 6077861
    Abstract: Novel compounds of Formula 1 are useful to treat disorders responsive to openers of the large conductance calcium-activated potassium channels: ##STR1## wherein "Het" is one of a select group of heterocyclic moieties; Z is independently for each occurrence selected from O or S; R.sup.a, R.sup.b and R.sup.c each are independently selected from hydrogen, halogen, OH, CF.sub.3, NO.sub.2, or ##STR2## provided R.sup.c is not hydrogen; and when R.sup.a and R.sup.b are hydrogen, R.sup.c may be a heterocyclic moiety selected from the group consisting of imidazol-1-yl, morpholinomethyl, N-methylimidazol-2-yl, and pyridin-2-yl; R.sup.d and R.sup.e each are independently selected from hydrogen, halogen, CF.sub.3, NO.sub.2 or imidazol-1-yl; m, n and p each are independently selected from an integer of O or 1; and R.sup.f and R.sup.g each are independently hydrogen; C.sub.1-4 alkyl; or R.sup.f and R.sup.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: June 20, 2000
    Assignee: Bristol-Myers Squibb Company
    Inventors: Jeffrey L. Romine, Scott W. Martin, Piyasena Hewawasam, Nicholas A. Meanwell, Valentin K. Gribkoff, John E. Starrett, Jr.
  • Patent number: 6034113
    Abstract: The present invention provides novel oxadiazolone derivatives having the general formula ##STR1## wherein A, B, D and R are as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of the large conductance calcium-activated potassium channels.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: March 7, 2000
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Min Ding, John E. Starrett, Jr.
  • Patent number: 5977150
    Abstract: The present invention provides novel amino acid derivatives having the general formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of potassium channels.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: November 2, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Xi Chen, John E. Starrett, Jr.
  • Patent number: 5972961
    Abstract: The present invention provides novel 4-aryl-3-aminoquinolin-2-one derivatives having the general formula ##STR1## wherein R, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are as defined herein, or a non-toxic pharmaceutically acceptable salt thereof which are modulators of the large conductance calcium-activated K.sup.+ channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: October 26, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, John E. Starrett, Jr., Stephen G. Swartz
  • Patent number: 5948802
    Abstract: The present invention provides novel benzoate derivatives having the general formula ##STR1## wherein R is as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of potassium channels.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: September 7, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Xi Chen, Min Ding, John E. Starrett, Jr.
  • Patent number: 5939405
    Abstract: The present invention provides novel phosphate derivatives having the general formula wherein A, R.sup.1 and R.sup.2 are as defined herein, or a nontoxic pharmaceutically acceptable salt or solvate thereof and are useful in the treatment of disorders which are responsive to the opening of potassium channels.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: August 17, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: John E. Starrett, Jr., Piyasena Hewawasam, Dalton King
  • Patent number: 5892106
    Abstract: The present invention relates to novel intermediates of the formula ##STR1## wherein the wavy bond () represents the racemate, the (R)-enantiomer or the (S)-enantiomer; and R is hydrogen, a carboxyl-protecting group or a cation of an addition salt; or solvate thereof; and to the use thereof in a process for the preparation of certain 3-fluoro oxindole derivatives.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: April 6, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Yadagiri R. Pendri, Eduardo J. Martinez, John K. Thottathil, Piyasena Hewawasam
  • Patent number: 5869509
    Abstract: Novel compounds of Formula 1 are useful to treat disorders responsive to openers of the large conductance calcium-activated potassium channels: ##STR1## wherein "Het" is one of a select group of heterocyclic moieties; Z is independently for each occurrence selected from O or S; R.sup.a, R.sup.b and R.sup.c each are independently selected from hydrogen, halogen, OH, CF.sub.3, ##STR2## provided R.sup.c is not hydrogen; and when R.sup.a and R.sup.b are hydrogen, R.sup.c may be a heterocyclic moiety selected from the group consisting of imidazol-1-yl, morpholinomethyl, N-methylimidazol- 2-yl, and pyridinyl; R.sup.d and R.sup.e each are independently selected from hydrogen, halogen, CF.sub.3, NO.sub.2 or imidazol-1-yl; m, n and p each are independently selected from an integer of O or 1; and R.sup.f and R.sup.g each are independently hydrogen; C.sub.1-4 alkyl; or R.sup.f and R.sup.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: February 9, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Jeffrey L. Romine, Scott W. Martin, Piyasena Hewawasam, Nicholas A. Meanwell, Valentin K. Gribkoff, John E. Starrett, Jr.
  • Patent number: 5808095
    Abstract: The present invention relates to novel intermediates of the formula ##STR1## wherein the wavy bond () represents the racemate, the (R)-enantiomer or the (S)-enantiomer; and R is hydrogen, a carboxyl-protecting group or a cation of an addition salt; or solvate thereof; and to the use thereof in a process for the preparation of certain 3-fluoro oxindole derivatives.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: September 15, 1998
    Assignee: Bristol-Myers Squibb Company
    Inventors: Yadagiri R. Pendri, Eduardo J. Martinez, John K. Thottathil, Piyasena Hewawasam
  • Patent number: 5602169
    Abstract: There is provided novel substituted 3-phenyl oxindole derivatives of the formula ##STR1## whereinR is hydrogen, hydroxy or fluoro;R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, C.sub.1-4 alkyl, halogen, trifluoromethyl, phenyl, p-methylphenyl or p-trifluoromethylphenyl; or R.sup.1 and R.sup.2, R.sup.2 and R.sup.3 or R.sup.3 and R.sup.4 are joined together to form a benzo fused ring;R.sup.5 is hydrogen or C.sub.1-4 alkyl; andR.sup.6 is chlorine or trifluoromethyl; or a nontoxic pharmaceutically acceptable salt, solvate or hydrate thereof, which are openers of the large-conductance calcium-activated potassium channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: February 11, 1997
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Nicholas A. Meanwell, Valentin K. Gribkoff
  • Patent number: 5565483
    Abstract: There is provided novel substituted 3-phenyl oxindole derivatives of the formula ##STR1## wherein R is hydrogen, hydroxy or fluoro; R.sup.1, R.sup.2, R.sup.3and R.sup.4 each are independently hydrogen, C.sub.1-4 alkyl, halogen, trifluoromethyl, phenyl, p-methylphenyl or p-trifluoromethylphenyl; or R.sup.1 and R.sup.2, R.sup.2 and R.sup.3 or R.sup.3 and R.sup.4 are joined together to form a benzo fused ring;R.sup.5 is hydrogen or C.sub.1-4 alkyl; andR.sup.6 is chlorine or trifluoromethyl;or a nontoxic pharmaceutically acceptable salt, solvate or hydrate thereof, which are openers of the large-conductance calcium-activated potassium channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 15, 1996
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Nicholas A. Meanwell, Valentin K. Gribkoff
  • Patent number: 5348960
    Abstract: A series of 1,3-dihydro-2H-imidazo[4,5-b]quinolin-2-ones having enhanced water solubility bioavailability and metabolic stability is disclosed in the Formula I ##STR1## wherein R.sup.1 is H, or C.sub.1 -C.sub.4 lower alkyl;R.sup.2 is H, or (CH.sub.2).sub.m R.sup.3 ;R.sup.3 is tetrahydro-2H-pyranyl, C.sub.1 -C.sub.8 alkyl, C.sub.4 -C.sub.8 cycloalkyl, or substituted or unsubstituted phenyl, wherein the substituents are halogen, alkoxy, or trifluoromethyl;m is an integer of 1-3; andn is an integer of 1-5;or pharmaceutically acceptable salt thereof.The compounds are useful as inhibitors of ADP-induced blood platelet aggregation in human platelet-rich plasma.
    Type: Grant
    Filed: August 30, 1993
    Date of Patent: September 20, 1994
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Nicholas A. Meanwell
  • Patent number: 5208237
    Abstract: A novel series of 1,3-dihydro-2H-imidazo[4,5-b]quinolin-2-ones having enhanced water solubility bioavailability and metabolic stability is disclosed in the Formula I ##STR1## wherein R.sup.1 is H, or C.sub.1 -C.sub.4 lower alkyl;R.sup.2 is H, (CH.sub.2).sub.m R.sup.3 ; benzoxazol-2yl, or benzothiazol2-yl;R.sup.3 is C.sub.1 -C.sub.8 alkyl, C.sub.4 -C.sub.8 cycloalkyl, or substituted or unsubstituted phenyl, wherein the substituents are halogen, alkoxy or trifluoromethyl;m is an integer of 1-3; andn is an integer of 1-5;or pharmaceutically acceptable salt thereof.The compounds are useful as inhibitors of ADP-induced blood platelet aggregation in human platelet-rich plasma.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: May 4, 1993
    Assignee: Bristol-Meyers Squibb Company
    Inventors: Piyasena Hewawasam, Nicholas A. Meanwell
  • Patent number: 5158958
    Abstract: A novel series of 1,3-dihydro-2H-imidazo [4,5-b]quinolin-2-ones having enhanced water solubility bioavailability and metabolic stability is disclosed in the Formula I ##STR1## wherein R.sup.1 is H, or C.sub.1 -C.sub.4 lower alkyl;R.sup.2 is H, or (CH.sub.2).sub.m R.sup.3 ;R.sup.3 is tetrahydro-2H-pyranyl, C.sub.1 -C.sub.8 alkyl, C.sub.4 -C.sub.8 cycloalkyl, or substituted or unsubstituted phenyl in which the substituents are halogen, alkoxy, or trifluoromethyl;m is an integer of 1-3; and n is an integer of 1-5; or pharmaceutically acceptable salt thereof.the compounds are useful as inhibitors of ADP-induced blood platelet aggregation in human platelet-rich plasma.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: October 27, 1992
    Assignee: Bristol-Myers Squibb Company
    Inventors: Piyasena Hewawasam, Nicholas A. Meanwell