Patents by Inventor Laszlo Legradi

Laszlo Legradi 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: 5639905
    Abstract: Process for the preparation of N-phenyl-N-methoxyacetyl-DL-alanine methyl ester derivatives of the formula (I). ##STR1## wherein R is a C.sub.1-4 alkyl residue; and n is a cardinal number between from 1 to 3,which comprises reacting an N-methoxyacetyl derivative of the formula (II). ##STR2## wherein R and n are as defined above, with a stoichiometric amount of an alkaline metal alkoxide, at a temperature between 80.degree. C. and 150.degree. C., until completion of the removal of the alkanol present in the system, then reacting the thus obtained alkaline metal salt of the compound of formula (II) directly or after isolation with a methyl DL-x-halopropionate.
    Type: Grant
    Filed: September 13, 1994
    Date of Patent: June 17, 1997
    Assignee: Nitrokemia Ipartelepek
    Inventors: Lajos Nagy, Jeno Pelyva, Pal Agocs, Csaba Soptei, Judit Benczik nee Pasztor, Zoltan Kolonics, Sandor Balint, Dezso Sebok, Jolan Cseke, Tibor Kranitz, Laszlo Legradi
  • Patent number: 4968840
    Abstract: A process for preparing methoxyacetic acid by reacting monochloroacetic acid with sodium methylate, in a methanolic solvent at increased temperature. Methanol is distilled off and methoxyacetic acid methylester is added to the residue. The stirrable mixture is contacted with dry hydrochloric acid gas. The methoxyacetic acid methylester is distilled off after removing the precipitated sodium chloride, to recover the desired product.
    Type: Grant
    Filed: July 13, 1989
    Date of Patent: November 6, 1990
    Assignee: Nitrokemia Ipartelepek
    Inventors: Pal Agocs, Lajos Nagy, Jeno Pelyva, Laszlo Legradi, Zoltan Kolonics, Csaba Soptei
  • Patent number: 4859772
    Abstract: The present invention relates to a process for the preparation of 3-isopropyl-benzo-2-thia-1,3-diazinone-(4)-2,2-dioxide which comprises preparing isopropyl sulfamoyl chloride in one step by reacting N,N'-diisopropyl-urea with phosphorus trichloride and chlorine in the presence of oleum and sulfuric acid and condensing the so obtained isopropyl sulfamoyl chloride at room temperature without any solvent in the presence of an excess of N,N-diethyl aniline with anthranylic acid methyl ester and subjecting the thus obtained N-isopropyl-N'-o-carbomethoxy-phenyl-sulfamide to cyclization in the presence of sodium methylate, extracting the obtained crude 3-isopropyl-benzo-2-thia-1,3-diazinone-(4)-2,2-dioxide with a mixture of methanol and water and after adding water to the aqueous-methanolic mixture and sedimenting the contaminations isolating a product of high purity.
    Type: Grant
    Filed: July 15, 1987
    Date of Patent: August 22, 1989
    Assignee: Nitro Kemia Ipartelepek
    Inventors: Jeno Pelyva, K. Istvan Vecsey, Zoltan Kolonics, Laszlo Legradi, Lajos Nagy, Andras Horvath, Ferenc Fodor, deceased, Csaba Soptei, Dezso Sebok, Elemer Tomordi, Laszlo Lendvai, Bela Karacsonyi, Erzsebet Dioszegi