Patents by Inventor Theodor Pfister

Theodor Pfister 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: 5221317
    Abstract: Herbicidally active sulphonylamino guanidinoazines of the formula ##STR1## in which R.sup.1 stands for an optionally substituted radical from the series comprising alkyl, aralkyl, aryl and hetaryl,R.sup.2 stands for an optionally substituted radical from the series comprising alkyl, aralkyl, aryl, hetaryl and dialkylamino,R.sup.3 stands for hydrogen, halogen, hydroxyl, alkyl, halogenaoalkyl, alkoxyalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,R.sup.5 stands for hydrogen, halogen, hydroxyl, alkyl, alkoxy, halogenoalkoxy, alkylthio, alkylamino or dialkylamino, andM stands for hydrogen, a metal equivalent, an ammonium equivalent, an alkylammonium equivalent, a dialkylammonium equivalent, or a trialkylammonium equivalent.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: June 22, 1993
    Assignee: Bayer Aktiengesellschaft
    Inventors: Klaus-Helmut Muller, Christa Fest, Rolf Kirsten, Theodor Pfister, Hans-Jochem Riebel, Hans-Joachim Santel, Robert R. Schmidt, Harry Strang, Joachim Kluth, Klaus Lurssen, Ernst R. Gesing
  • Patent number: 5213608
    Abstract: Herbicidal substituted sulphonylamidinohydrazones of the formula ##STR1## in which R.sup.1 represents in each case optionally substituted aryl, aralkyl or heteroaryl,R.sup.2 represents hydrogen, or represents in each case optionally substituted alkyl, aryl or aralkyl,R.sup.3 represents hydrogen, or represents in each case optionally substituted alkyl, alkenyl, alkadienyl, alkinyl, (hetero)aryl, aralkyl, aralkenyl, alkoxy, alkoxycarbonyl or dialkylamino, or together with R.sup.2 represents optionally substituted alkanediyl,R.sup.4 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxyalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,X represents nitrogen or a --CH group,Y represents nitrogen or a --CR.sup.5 group whereR.sup.5 represents hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl, andZ represents nitrogen or a --CR.sup.6 group whereR.sup.
    Type: Grant
    Filed: July 16, 1992
    Date of Patent: May 25, 1993
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Ernst R. F. Gesing, Rolf Kirsten, Joachim Kluth, Reinhard Lantzsch, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Frank Rosenfeldt, Hans-Joachim Santel, Klaus Lurssen, Robert R. Schmidt
  • Patent number: 5167692
    Abstract: Herbicidal substituted sulphonylamidinohydrazones of the formula ##STR1## in which R.sup.1 represents in each case optionally substituted aryl, aralkyl or heteroaryl,R.sup.2 represents hydrogen, or represents in each case optionally substituted alkyl, aryl or aralkyl,R.sup.3 represents hydrogen, or represents in each case optionally substituted alkyl, alkenyl, alkadienyl, alkinyl, (hetero)aryl, aralkyl, aralkenyl, alkoxy, alkoxycarbonyl or dialkylamino, or together with R.sup.2 represents optionally substituted alkanediyl,R.sup.4 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxyalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,X represents nitrogen or a --CH group, Y represents nitrogen or a --CR.sup.5 group whereR.sup.5 represents hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl, andZ represents nitrogen or a --CR.sup.6 group whereR.sup.
    Type: Grant
    Filed: September 17, 1990
    Date of Patent: December 1, 1992
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Ernst R. F. Gesing, Rolf Kirsten, Joachim Kluth, Reinhard Lantzsch, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Frank Rosenfeldt, Hans-Joachim Santel, Klaus Lurssen, Robert R. Schmidt
  • Patent number: 4990637
    Abstract: Herbicidally active novel substituted 1-benzylsulphonyl-3-heteroaryl(thio)-ureas of the formula ##STR1## in whichQ.sub.1 represents oxygen or sulphur,R.sup.1 represents hydrogen, or represents optionally substituted radicals from the series comprising alkyl, alkenyl, alkynyl and aralkyl,R.sup.2 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,R.sup.3 represents hydrogen or alkyl,R.sup.4 represents halogenoalkyl,X represents nitrogen or a --CH grouping,Y represents nitrogen or a --CR.sup.5 grouping,R.sup.5 represents hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl,Z represents nitrogen or a --CR.sup.6 grouping, andR.sup.6 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, alkylamino or dialkylamino,and salts thereof with metals and basic organic nitrogen compounds. The benzylsulphonyl moieties are also new.
    Type: Grant
    Filed: January 30, 1990
    Date of Patent: February 5, 1991
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Ernst Kysela, Hans-Joachim Santel, Robert R. Schmidt, Robert H. Strang
  • Patent number: 4988379
    Abstract: The invention relates to new sulphonyliso(thio)-urea derivatives of the general formula (I) ##STR1## in which R.sup.1 represents an optionally substituted radical from the series comprising alkyl, aralkyl, aryl and heteroaryl,R.sup.2 represents an optionally substituted and/or optionally fused 6-membered aromatic heterocyclic radical containing at least one nitrogen atom,R.sup.3 represents an optically substituted aromatic or heteroaromatic radical,X represents oxygen or sulphur andM represents hydrogen or an equivalent of a metal,and adducts of compounds of the formula (I) with strong acids, processes for their preparation, and their use as herbicides.
    Type: Grant
    Filed: January 4, 1989
    Date of Patent: January 29, 1991
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Joachim Diehr, Christa Fest, Rolf Kirsten, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Uwe Priesnitz, Hans-Jochem Riebel, Wolfgang Roy, Hans-Joachim Santel, Robert R. Schmidt, Ludwig Eue
  • Patent number: 4969948
    Abstract: Herbicidal and plant growth-regulating substituted phenoxyphenylsulphonylazoles of the formula ##STR1## in which R.sup.1 represents hydrogen, halogen, cyano or trifluoromethyl,R.sup.2 represents hydrogen or halogen,R.sup.3 represents halogen, cyano, trifluoromethyl, trifluoromethoxy or trifluoromethylsulphonyl,R.sup.4 represents hydrogen or halogen,R.sup.5 represents hydrogen or halogen,R.sup.6 represents hydrogen, halogen, cyano, nitro or amino andAz represents optionally substituted azolyl.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: November 13, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Michael Haug, Theodor Pfister, Hans-Joachim Santel, Robert R. Schmidt, Klaus Lurssen, Harry Strang
  • Patent number: 4952233
    Abstract: Herbicidally active sulphonylamino guanidinoazines of the formula ##STR1## in which R.sup.1 stands for a optionally substituted radical from the series comprising alkyl, aralkyl, aryl and hetaryl, R.sup.2 stands for an optionally substituted radical from the series comprising alkyl, aralkyl, aryl, hetaryl and dialkylamino, R.sup.3 stands for hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxyalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,X stands for nitrogen or a --CH-- grouping,Y stands for nitrogen or a --CR.sup.4 -- grouping,whereinR.sup.4 stands for hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl,Z stands for mitrogen or a --CR.sup.5 -- grouping,whereinR.sup.
    Type: Grant
    Filed: August 2, 1988
    Date of Patent: August 28, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Klaus-Helmut Muller, Christa Fest, Rolf Kirsten, Theodor Pfister, Hans-Jochem Riebel, Hans-Joachim Santel, Robert R. Schmidt, Harry Strang
  • Patent number: 4927454
    Abstract: Herbicidally active novel substituted 1-benzylsulphonyl-3-heteroaryl(thio)-ureas of the formula ##STR1## in which Q represents oxygen or sulphur,R.sup.1 represents hydrogen, or represents optionally substituted radicals from the series comprising alkyl, alkenyl, alkynyl and aralkyl,R.sup.2 represents hydrogen, halogen, hydroxy, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,R.sup.3 represents hydrogen or alkyl,R.sup.4 represents halogenoalkyl,X represents nitrogen or a --CH grouping,Y represents nitrogen or a --CR.sup.5 grouping,R.sup.5 represents hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl,Z represents nitrogen or a --CR.sup.6 grouping, andR.sup.6 represents hydrogen, halogen, hydroxy, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, alkylamino or dialkylamino,and salts thereof with metals and basic organic nitrogen compounds. The benzylsulphonyl moieties are also new.
    Type: Grant
    Filed: November 8, 1988
    Date of Patent: May 22, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Ernst Kysela, Hans-Joachim Santel, Robert R. Schmidt, Robert H. Strang
  • Patent number: 4911752
    Abstract: A method of combating unwanted vegetation which comprises applying to such vegetation or to a locus from which it is desired to exclude such vegetation a herbicidally effective amount of a halogenoalkoxyphenylsulphonylisothioureidoazine of the formula ##STR1## in which R.sup.1 represents halogeno-C.sub.1 -C.sub.4 -alkoxy,R.sup.2 represents hydrogen, halogen, hydroxyl, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -halogenoalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -halogenoalkoxy, C.sub.1 -C.sub.4 -alkylthio, C.sub.1 -C.sub.4 -halogenoalkylthio, amino, C.sub.1 -C.sub.4 -alkylamino or di-(C.sub.1 -C.sub.4 -alkyl)amino,X represents nitrogen or a --CH-- grouping,Y represents nitrogen or a --CR.sup.4 -- grouping,whereinR.sup.4 represents hydrogen, halogen, cyano, C.sub.1 -C.sub.4 -alkyl, formyl, C.sub.1 -C.sub.4 -alkyl-carbonyl or C.sub.1 -C.sub.4 -alkoxy-carbonyl, andZ represents nitrogen or a --CR.sup.5 -- grouping,whereinR.sup.5 represents hydrogen, halogen, hydroxyl, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.
    Type: Grant
    Filed: March 15, 1988
    Date of Patent: March 27, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Hans-Joachim Santel, Robert R. Schmidt
  • Patent number: 4880932
    Abstract: A plant growth regulating compound of the formula ##STR1## in which R.sup.2 is an optionally substituted nitrogen heterocyclic radical,R.sup.3 is hydrogen, alkyl, cycloalkyl, alkenyl, alkinyl or aralkyl, andR.sup.4 is hydrogen, or if R.sup.3 is not hydrogen R.sup.4 may be hydroxyl or a variety of radicals, orR.sup.3 and R.sup.4 together may form a ring,or an acid adduct thereof.
    Type: Grant
    Filed: April 29, 1987
    Date of Patent: November 14, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Koichi Moriya, Theodor Pfister, Hans-Jochem Riebel, Ludwig Eue, Robert R. Schmidt, Klaus Lurrsen
  • Patent number: 4844730
    Abstract: A plant growth regulating compound of the formula ##STR1## in which R.sup.2 is an optionally substituted nitrogen heterocyclic radical,R.sup.3 is hydrogen, alkyl, cycloalkyl, alkenyl, alkinyl or aralkyl, andR.sup.4 is hydrogen, or if R.sup.3 is not hydrogen R.sup.4 may be hydroxyl or a variety of radicals, orR.sup.3 and R.sup.4 together may form a ring,or an acid adduct thereof.
    Type: Grant
    Filed: July 27, 1988
    Date of Patent: July 4, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Koichi Moriya, Theodor Pfister, Hans-Jochem Riebel, Ludwig Eue, Robert R. Schmidt, Klaus Lurssen
  • Patent number: 4840661
    Abstract: The invention relates relates to new sulphonyliso(thio)-urea derivatives of the general formula (I) ##STR1## in which R.sup.1 represent an optionally substituted radical from the series comprising alkyl, aralkyl, aryl and heteroarylR.sup.2 represents an optionally substituted and/or optionally fused 6-membered aromatic heterocyclic radial containing at least one nitrogen atom,R.sup.3 represents an optically substituted aromatic or heteroaromatic radical,X represents oxygen or sulphur andM represents hydrogen or an equivalent of a metal, and adducts of compounds of the formula (I) with strong acids, processes for their prepartion, and their use as herbicides.
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: June 20, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Joachim Diehr, Christa Fest, Rolf Kristen, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Uwe Priesnitz, Hans-Jochem Riebel, Wolfgang Roy, Hans-Joachim Santel, Robert R. Schmidt, Ludwig Eue
  • Patent number: 4820337
    Abstract: Herbicidally active 1-(2-oxyaminosulphenylphenylsulphonyl)-3-triazinyl-ureas of the formula ##STR1## in which X is nitrogen,Y is nitrogn,Z is C-R.sup.6 andR.sup.1, R.sup.2, R.sup.4 and R.sup.6 are various organic radicals.
    Type: Grant
    Filed: March 24, 1987
    Date of Patent: April 11, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Joachim Diehr, Christa Fest, Rolf Kirsten, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Uwe Priesnitz, Hans-Jochem Riebel, Wolfgang Roy, Hans-Joachim Santel, Robert R. Schmidt
  • Patent number: 4806147
    Abstract: Herbicidally active novel substituted 1-benzylsulphonyl-3-heteroaryl(thio)-ureas of the formula ##STR1## in which Q represents oxygen or sulphur,R.sup.1 represents hydrogen, or represents optionally substituted radicals from the series comprising alkyl, alkenyl, alkynyl and aralkyl,R.sup.2 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, halogenoalkylthio, amino, alkylamino or dialkylamino,R.sup.3 represents hydrogen or alkyl,R.sup.4 represents halogenoalkyl,X represents nitrogen or a --CH grouping,Y represents nitrogen or a --CR.sup.5 grouping,R.sup.5 represents hydrogen, halogen, cyano, alkyl, formyl, alkyl-carbonyl or alkoxy-carbonyl,Z represents nitrogen or a --CR.sup.6 grouping, andR.sup.6 represents hydrogen, halogen, hydroxyl, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio, alkylamino or dialkylamino,and salts thereof with metals and basic organic nitrogen compounds. The benzylsulphonyl moieties are also new.
    Type: Grant
    Filed: December 9, 1987
    Date of Patent: February 21, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christa Fest, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Ernst Kysela, Hans-Joachim Santel, Robert R. Schmidt, Robert H. Strang
  • Patent number: 4802910
    Abstract: Novel herbicides of the formula ##STR1## in which R.sup.1 represents an organic radical,R.sup.2 represents hydrogen or an organic radical,R.sup.3 represents an organic radical or an amino radical,R.sup.4 represents hydrogen, an organic radical, an ether radical or an amino radical,X represents N or CH,Y and Z each represent N, CH or a substituted C radical, andM is H, a metal ion or an acyl radical, or a strong acid adduct thereof. Some intermediates are also new.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: February 7, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Rolf Kirsten, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Hans-Jochem Riebel, Hans-Joachim Santel, Robert R. Schmidt
  • Patent number: 4797484
    Abstract: A process for the preparation of a guanidine derivative of the formula ##STR1## in which R.sup.1 represents hydrogen or the radical R.sup.5 --S(O).sub.m --,m represents the numbers zero, 1 or 2 andR.sup.5 represents an optionally substituted radical from the series comprising alkyl, aralkyl, aryl and heteroaryl,R.sup.2 represents a six-membered aromatic heterocyclic structure which contains at least one nitrogen atom and is substituted, andR.sup.8 represents an optionally substituted radical from the series comprising C.sub.1 -C.sub.6 -alkyl, alkenyl, alkinyl, cycloalkyl, phenylalkyl and aryl,which comprises reacting a guanidine derivative of the formula ##STR2## with one or two molar equivalent(s), respectively, of a halogen/sulphur compound of the formulaR.sup.5 --S(O).sub.m --X.sup.1in whichX.sup.1 represents fluorine, chlorine or bromine.The compounds are herbicidally active.
    Type: Grant
    Filed: January 16, 1987
    Date of Patent: January 10, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Koichi Moriya, Theodor Pfister, Hans-Jochem Riebel, Ludwig Eue, Robert R. Schmidt, Klaus Lurssen
  • Patent number: 4787929
    Abstract: Novel phenoxypropionyloxyalkanephosphonates of the formula ##STR1## in which R is optionally substituted alkyl andA is alkanediyl substituted by an optionally substituted pyridyl and use of such new compounds as herbicides.
    Type: Grant
    Filed: January 7, 1987
    Date of Patent: November 29, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Theodor Pfister, Heinz Forster, Ludwig Eue, Robert R. Schmidt, Hans-Joachim Santel
  • Patent number: 4780126
    Abstract: 3-Substituted 1-(2-halogenoalkoxy-benzenesulphonyl)-3-heteroaryl-(thio)urea herbicides of the formula ##STR1## in which (A)R is CF.sub.3,Q is O,R.sup.1 is CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7 -n, C.sub.3 H.sub.7 -i, CH.sub.2 --CH.dbd.CH.sub.2, CH.sub.2 --C.tbd.CH or CH.sub.2 --C.sub.6 H.sub.5,R.sup.2 is CH.sub.3, OCH.sub.3, OC.sub.2 H.sub.5, SCH.sub.3, NH--CH.sub.3 or NH--C.sub.2 H.sub.5,X is N,Y is N andZ is C--CH.sub.3, C--C.sub.2 H.sub.5, C--OCH.sub.3 or C--OC.sub.2 H.sub.5 ; or(B)R is CF.sub.3,Q is O,R.sup.1 is CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7 -n, C.sub.3 H.sub.7 -i, CH.sub.2 --CH.dbd.CH.sub.2, CH.sub.2 --C.tbd.CH or CH.sub.2 --C.sub.6 H.sub.5,R.sup.2 is CH.sub.3, OCH.sub.3 or OC.sub.2 H.sub.5,X is N,Y is C--H andZ is C--C.sub.2 H.sub.5, C--OCH.sub.3 or C--OC.sub.2 H.sub.5 ; or(C)R is CH.sub.2 --CH.sub.2 Cl,Q is O,R.sup.1 is CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7 -n, C.sub.3 H.sub.7 -i, CH.sub.2 --CH.dbd.CH.sub.2, CH.sub.2 --C.tbd.CH or CH.sub.2 --C.sub.6 H.sub.5,R.sup.2 is CH.sub.
    Type: Grant
    Filed: June 9, 1987
    Date of Patent: October 25, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Joachim Diehr, Christa Fest, Rolf Kirsten, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Uwe Priesnitz, Hans-Jochem Riebel, Wolfgang Roy, Hans-Joachim Santel, Robert R. Schmidt, Ludwig Eue, Ernst Kysela
  • Patent number: 4769484
    Abstract: Herbicidally active phenoxybenzoic acid esters of the formula ##STR1## in which X represents hydrogen or halogen,A represents optionally branched C.sub.2 -C.sub.6 -alkanediyl,Q represents oxygen, sulphur, sulphinyl (SO) or sulphonyl (SO.sub.2),R.sup.1 represents hydrogen or methyl,R.sup.2 represents hydrogen or C.sub.1 -C.sub.4 -alkyl, andR.sup.3 and R.sup.4 are identical or different and represent hydrogen, halogen, cyano, nitro, C.sub.1 -C.sub.4 -alkyl, halogeno-C.sub.1 -C.sub.2 -alkyl, C.sub.1 -C.sub.4 -alkoxy, halogeno-C.sub.1 -C.sub.2 -alkoxy and C.sub.1 -C.sub.2 -alkoxycarbonyl.
    Type: Grant
    Filed: August 4, 1987
    Date of Patent: September 6, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Heinz Forster, Theodor Pfister, Hans-Joachim Santel, Robert R. Schmidt, Robert H. Strang
  • Patent number: RE33298
    Abstract: The invention relates to new 1-(2-oxyaminosulphonylphenylsulphonyl)-3-heteroaryl-ureas of the general formula (I) ##STR1## in which R.sup.1 represents an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkylalkyl, aralkyl and aryl,R.sup.2 represents hydrogen or an optionally substituted radical from the series comprising alkyl, alkenyl, alkinyl and aralkyl andR.sup.
    Type: Grant
    Filed: June 21, 1989
    Date of Patent: August 14, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-Joachim Diehr, Christa Fest, Rolf Kirsten, Joachim Kluth, Klaus-Helmut Muller, Theodor Pfister, Uwe Priesnitz, Hans-Jochem Riebel, Wolfgang Roy, Hans-Joachim Santel, Robert R. Schmidt