Patents by Inventor Nicholas J. Sisti

Nicholas J. Sisti 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: 6448417
    Abstract: The present invention relates to a method of producing paclitaxel or a paclitaxel analog comprising the esterification of C-7, C-10 di-CBZ 10-deacetylbaccatin III with an N-carbamate protected, C-2-protected 3-phenyl isoserine side chain. The C-7, C-10 carbobenzyloxy groups are then replaced with hydrogen and an acyl group is substituted at the C-3′ nitrogen. The resulting compound is acylated at the C-10 hydroxyl position, and deprotected at the C-2′ position by replacing the hydroxyl protecting group with hydrogen to produce paclitaxel or a paclitaxel analog. The present invention also relates to alternative methods of acylating a 10-hydroxy paclitaxel analog. The first method comprises dissolving a 10-hydroxy paclitaxel analog in an acceptable ether solvent therefor to form a first solution at a first temperature.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: September 10, 2002
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: Nicholas J. Sisti, Herbert R. Brinkman, James D. McChesney, Medhavi C. Chander, Xian Liang, Jan Zygmunt
  • Patent number: 6329378
    Abstract: Disclosed are pharmaceutical compositions comprising aryl and heteroaryl hydrazone, hydrazine and thiosemicarbazone derivatives of formulae I and II, and methods for using the compositions as antifungal agents. The invention also relates to novel aryl and heteroaryl hydrazone, hydrazine and thiosemicarbazone derivatives of formulae I and II, their preparation, to pharmaceutical compositions containing them, and to methods of using them to alleviate fungal infections.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: December 11, 2001
    Assignee: Anadys Pharmaceuticals, Inc.
    Inventors: Xiaodan Mei, Peng Wang, Andrei Caracoti, Pamela Mingo, Vincent Boyd, Robert Murray, Nicholas J. Sisti, Yi Bin Xiang, Shuhao Zhu, C. Richard Wobbe, Daniel Moore
  • Patent number: 6133462
    Abstract: A compound for use in the production of taxanes and intermediates therefor having the formula: ##STR1## wherein R is an alkyl group.
    Type: Grant
    Filed: September 2, 1997
    Date of Patent: October 17, 2000
    Assignees: NaPro BioTherapeutics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell
  • Patent number: 6107497
    Abstract: C7, C10 di-CBZ 10-deacetyl baccatin III of the formula: ##STR1## provides an intermediate for the production of docetaxel. A method of producing this C7, C10 di-CBZ 10-deacetyl Baccatin III is provided. Here, 10-deacetyl Baccatin III is acylated with at least 1.5 equivalents of n-butyl lithium and at least 1.5 equivalents of benzyl chloroformate in tetrahydrofuran. The 10-deacetyl Baccatin III may first be dissolved in tetrahydrofuran after which the n-butyl lithium is added followed by the addition of the benzyl chloroformate. The reaction is preferably at a reduced temperature of less than -20.degree. C. The resulting solution may be quenched with ammonium chloride and reduced to residue. The residue may then be redissolved in an organic solvent, washed, dried and recrystallized to purify the compound.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: August 22, 2000
    Assignees: NaPro BioTherapeutics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell, Madhavi C. Chander
  • Patent number: 6066749
    Abstract: A method of acylating C-2' O-protected-10-hydroxy taxol selectively at the C-10 hydroxyl position over the C-7 hydroxy position thereof to produce C-2' O-protected taxol is accomplished first by dissolving C-2' O-protected-10-hydroxy taxol in an acceptable ether solvent therefor, such as tetrahydrofuran, to form a first solution at a first temperature. The first solution is then cooled to a second temperature, and a lithium base, preferably n-butyl lithium, is added to form an intermediate compound having a lithium alkoxide at the C-10 position thereof. An acylating agent, such as acetyl chloride, is then added. The resulting solution may be quenched, for example with ammonium chloride, to eliminate excess of the acylating agent and the lithium base. The result is a solution containing C-2' O-protected taxol. This solution may then be washed, concentrated and purified. The present invention is also directed to C-10 lithium alkoxide intermediate compounds for the production of paclitaxel.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: May 23, 2000
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: Nicholas J. Sisti, Herbert R. Brinkman, James D. McChesney, Madhavi C. Chander, Xian Liang, Jan Zygmunt
  • Patent number: 6048990
    Abstract: A method of acylating C-2' O-protected-10-hydroxy taxol selectively at the C-10 hydroxyl position over the C-7 hydroxy position thereof to produce C-2' O-protected taxol is accomplished first by dissolving C-2' O-protected-10-hydroxy taxol in an acceptable ether solvent therefor, such as tetrahydrofuran. A lithium salt, preferably lithium chloride, is added. A trialkylamine base or pyridine is next added, followed by the addition of an acylating agent, such as acetyl chloride. The resulting solution may be quenched, for example with ammonium chloride, to eliminate excess of the acylating agent. This solution may then be diluted with ethyl acetate to form an organic phase and an aqueous phase, with the organic phase being washed and thereafter reduced. Recrystallization and column chromatography may be employed to purify the C-2' O-protected taxol.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: April 11, 2000
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: Xian Liang, Jan Zygmunt, Nicholas J. Sisti, Madhavi C. Chander, Herbert R. Brinkman, James D. McChesney
  • Patent number: 5973170
    Abstract: A chemical compound having the formula: wherein R is an alkyl group and M.sup.+ counterion is an alkali metal, and a process of making the same.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: October 26, 1999
    Assignees: NaPro BioTherapuetics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell
  • Patent number: 5948919
    Abstract: An efficient protocol for the synthesis of taxol, taxol analogs and their intermediates is described. The process incudes the attachment of the taxol A-ring side chain to baccatin III and for the synthesis of taxol and taxol analogs with variable A-ring side chain structures. A rapid and highly efficient esterification of O-protected isoserine and 3-phenylisoserine acids having N-benzyoloxycarbonyl groups to the C-13 hydroxyl of 7-O-protected baccatin III is followed by a deprotection-acylation sequence to make taxol, celphalomanninne and various analogs, including photoaffinity labeling candidates.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 7, 1999
    Assignees: NaPro BioTherapeutics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell, Madhavi C. Chander
  • Patent number: 5914411
    Abstract: A method of acylating 10-deacetylbaccatin III at the C-10 position over the C-7 hydroxy position thereof to produce baccatin IIII is accomplished first by dissolving 10-deacetylbaccatin III in an acceptable ether solvent therefor, such as tetrahydrofuran. A lithium salt, preferably lithium chloride, is added. A trialkylamine base or pyridine is next added, followed by the addition of an acylating agent, such as acetyl chloride. The resulting solution may be quenched, for example with ammonium chloride, to eliminate excess of the acylating agent. The result is baccatin III in solution. This solution may then be diluted with ethyl acetate to form an organic phase and an aqueous phase, with the organic phase being washed and thereafter reduced. Recrystallization and column chromatography may be employed to purify the baccatin III.
    Type: Grant
    Filed: January 21, 1998
    Date of Patent: June 22, 1999
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: Nicholas J. Sisti, Jan Zygmunt, Herbert R. Brinkman, Madhavi C. Chander, Xian Liang, James D. McChesney
  • Patent number: 5750737
    Abstract: A method for producing paclitaxel is accomplished by first esterifying C-7-CBZ baccatin III with a C3'-N-CBZ-C2'-O-protected (2R, 3S)-3-phenylisoserine side chain to form a first intermediate. Next, the carbobenzyloxy groups at C-7 and at the C3' nitrogen site of the first intermediate are respectively replaced with hydrogen and PhCO to produce a second intermediate that is next deprotected at C2' by replacing the protecting group with hydrogen. The C2' protecting group is a benzyl-type protecting group, preferably benzyloxymethyl or benzyl. Excess amounts, such as six equivalents, of the side chain are preferably employed. DMAP and a dialkylcarbodiimide are also preferably used during esterification. Various preferred reaction temperatures, times, and purification steps are disclosed.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: May 12, 1998
    Inventors: Nicholas J. Sisti, Charles S. Swindell
  • Patent number: 5750736
    Abstract: A method of acylating 10-deacetylbaccatin III at the C-10 position over the C-7 hydroxy position thereof to produce baccatin III is accomplished first by dissolving 10-deacetylbaccatin III in an anhydrous ether solvent, such as tetrahydrofuran, at a reduced temperature, preferably -78.degree. C. At least an equivalent of a lithium base, preferably about two equivalents n-butyl lithium, is next added followed by the addition of an acylating agent, such as acetyl chloride. The resulting solution is quenched, for example with ammonium chloride, to eliminate excess of the lithium base and the acylating agent. The result is baccatin III in solution. The baccatin III may be recovered by removing the ether solvent under vacuum to produce a residue that may then be dissolved, for example in ethyl acetate, with this solution being washed to remove unwanted salt compounds. Recrystallization and column chromatography may be employed to purify the baccatin III.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: May 12, 1998
    Assignee: NaPro BioTherapeutics, Inc.
    Inventor: Nicholas J. Sisti
  • Patent number: 5688977
    Abstract: A method of producing docetaxel comprises the esterification of C7, C10 di-CBZ 10-deacetyl baccatin III and an N-CBZ C2'-protected 3-phenyl isoserine side chain wherein C2' is protected by a hydrogenatable benyl-type protecting group. The C7, C10 carbobenzyloxy groups are then replaced with hydrogen and the carbobenzyloxy group at the C3' nitrogen site is replaced with t-butoxycarbonyl. Finally, the resulting compound is deprotected at C2' by replacing the benzyl-type protecting group with hydrogen to produce docetaxel. The esterification preferably employs an excess, such as six equivalents, of the side chain for each equivalent of the C7, C10 di-CBZ 10-deacetyl baccatin III. Benzyloxymethyl is the preferred protecting group at C2'.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: November 18, 1997
    Assignees: NaPro BioTherapeutics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell
  • Patent number: 5684175
    Abstract: The synthesis of paclitaxel obtained from the semi-synthesis of taxol using a protected baccatin III backbone which is esterified with a suitably protected side chain acid, thereby producing an intermediate which may be acylated and deprotected to produce paclitaxel.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 4, 1997
    Assignees: NaPro BioTherapeutics, Inc., Bryn Mawr College
    Inventors: Nicholas J. Sisti, Charles S. Swindell, Madhavi C. Chander
  • Patent number: 5675025
    Abstract: An efficient protocol for the synthesis of taxol, taxol analogs and their intermediates is described. The process includes the attachment of the taxol A-ring side chain to baccatin III and for the synthesis of taxol and taxol analogs with variable A-ring side chain structures. A rapid and highly efficient esterification of O-protected isoserine and 3-phenylisoserine acids having N-benzyoloxycarbonyl groups to the C-13 hydroxyl of 7-O-protected baccatin III is followed by a deprotection-acylation sequence to make taxol, celphalomanninne and various analogs, including photoaffinity labeling candidates.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 7, 1997
    Assignee: NaPro BioTherapeutics, Inc.
    Inventors: Nicholas J. Sisti, Charles S. Swindell, Madhavi C. Chander