Patents by Inventor Frank Kavka

Frank Kavka 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).

  • Preparation of nalbuphine having low levels of .beta.-epimer
    Patent number: 5756745
    Abstract: A process is described for the synthesis of nalbuphine. The process results in a product having very low levels of the undesirable .beta.-epimer. The process is a five-step synthesis that begins with a compound such as an N,O.sup.3 -bis (alkoxycarbonyl) -14-hydroxynormorphinone.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: May 26, 1998
    Assignee: Mallinckrodt Medical, Inc.
    Inventor: Frank Kavka
  • Preparation of 14-hydroxy-N-ethoxy-carbonyl-norcodeinone
    Patent number: 4639520
    Abstract: N-ethoxycarbonyl-14-hydroxynorcodeinone is prepared by contacting N-ethoxycarbonyl-norcodeinone enol acetate with an aromatic or aliphatic mono-basic or poly-basic peroxy-acid under reaction conditions effective for substituting an --OH group in the 14-position of the norcodeinone enol acetate.In a preferred embodiment the reaction conditions include effecting the contacting in the presence of (A) a moderately strong acid having a pK.sub.a of from about 0.3 to about 3.5, (B) an inert organic solvent, and (C) in the substantial absence of water.Codeine is converted to noroxymorphone by an improved process employing the above method for introducing the 14-hydroxy group into the codeine derivative.
    Type: Grant
    Filed: March 27, 1984
    Date of Patent: January 27, 1987
    Assignee: Mallinckrodt, Inc.
    Inventor: Frank Kavka
  • Synthesis of dideoxyzearalane and related compounds
    Patent number: 4042602
    Abstract: A method is disclosed for preparing dideoxyzearalane and related compounds which comprises reacting a hexahydrozearalin with an organic sulfonyl chloride to form a sulfonate ester derivative; recovering the sulfonate ester derivative; and catalytically dehydrosulfonyloxylating and aromatizing the sulfonate ester derivative to form the desired product.
    Type: Grant
    Filed: November 4, 1976
    Date of Patent: August 16, 1977
    Assignee: IMC Chemical Group, Inc.
    Inventors: Donald Edwin Robertson, Wilbert Herbert Urry, Frank Kavka
  • Process for preparing zearalene type compounds
    Patent number: 3954805
    Abstract: Zearalene type compounds are prepared by treating zearalenone type compounds in a solvent selected from the group consisting of acetic anhydride, propionic anhydride, dioxane, ethyl acetate, ethyl ether, and tetrahydrofurane, under reducing conditions in the presence of reducing amounts of zinc and hydrogen halide.
    Type: Grant
    Filed: March 25, 1975
    Date of Patent: May 4, 1976
    Assignee: Commercial Solvents Corporation
    Inventor: Frank Kavka
  • Loudspeaker
    Patent number: D375499
    Type: Grant
    Filed: August 9, 1995
    Date of Patent: November 12, 1996
    Assignee: Meyer Sound Laboratories Incorporated
    Inventors: John D. Meyer, Jeffrey A. Weiner, Frank Kavka