Patents by Inventor Burton G. Christensen

Burton G. Christensen 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: 4617152
    Abstract: A process is described for selectively obtaining 1-.beta.-methylcarbapenem intermediates. The desired chirality is obtained through the hydrogenation of certain bicyclic .beta.-lactam ring structures containing an exocyclic methylene double bond alpha to the .beta.-lactam ring, in the presence of a Group VIII metal hydrogenation catalyst. The hydrogenation results in a mixture of .alpha.- and .beta.-methyl epimers having a high .beta./.alpha. epimeric ratio. New 1-.beta.-methylcarbapenem intermediates made by the process are also described.
    Type: Grant
    Filed: February 19, 1985
    Date of Patent: October 14, 1986
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Lovji D. Cama, Susan M. Schmitt
  • Patent number: 4610820
    Abstract: In a process for the total synthesis of thienamycin from L-aspartic acid via intermediate III: ##STR1## R=H, blocking group or salt cation there is disclosed a process for preparing III via ##STR2## wherein R is a protecting group.
    Type: Grant
    Filed: October 11, 1985
    Date of Patent: September 9, 1986
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe, Thomas N. Salzmann
  • Patent number: 4600713
    Abstract: Disclosed are 1-, 6- and 2-substituted-1-carba-2-penem-3-carboxylic acids of the following structure: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, cycloalkylalkyl, spirocycloalkyl, heterocyclyl, heteroaryl, aryl, and aralkyl. Such compounds as well as their pharmaceutically acceptable salt, ester and amide derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: December 5, 1983
    Date of Patent: July 15, 1986
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, David H. Shih
  • Patent number: 4595750
    Abstract: A process is described for selectively obtaining 1-.beta.-methylcarbapenem intermediates. The desired chirality is obtained through the hydrogenation of certain bicyclic .beta.-lactam ring structures containing an exocyclic methylene double bond alpha to the .beta.-lactam ring, in the presence of a Group VIII metal hydrogenation catalyst. The hydrogenation results in a mixture of .alpha.- and .beta.-methyl epimers having a high .beta./.alpha. epimeric ratio. New 1-.beta.-methylcarbapenem intermediates made by the process are also described.
    Type: Grant
    Filed: August 29, 1984
    Date of Patent: June 17, 1986
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Lovji D. Cama, Susan M. Schmitt
  • Patent number: 4582643
    Abstract: Disclosed are 1-substituted-6-(1-hydroxyethyl)-2-(2-aminoethylthio)-1-carbadethiapen-2-e m-3-carboxylic acids (I) and their pharmaceutically acceptable salts and esters which are useful as antibiotics; such compounds are prepared by total synthesis. ##STR1## wherein R.sup.1 and R.sup.2 are, inter alia, substituted and unsubstituted alkyl, aryl, aralkyl, cycloalkyl, cycloalkylalkyl and the spiro substituent formed by the joinder of R.sup.1 and R.sup.2.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: April 15, 1986
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, David H. Shih
  • Patent number: 4565808
    Abstract: 3-Phosphonate carbapenems of the Formula: wherein R.sup.1 is hydrogen, alkyl, amino, --NHCO-alkyl, hydroxy, alkoxy, halo, hydroxyalkyl, carboxyl or trifluoromethyl; R.sup.2 is alkyl, substituted alkyl, heterocyclic or substituted heterocyclic; R.sup.3 is hydrogen, alkyl or substituted alkyl; and M is a metal cation of H.sup.+ are disclosed. The compounds are useful as antibiotics.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: January 21, 1986
    Assignee: Merck & Co., Inc.
    Inventors: W. Alexander Andrus, Burton G. Christensen, James V. Heck
  • Patent number: 4544557
    Abstract: Disclosed is the antibiotic 6-(1-hydroxyethyl)-2-substituted-thio-3-tetrazolyl-1-carbadethiapen-2-em and its pharmaceutically acceptable salts (I): ##STR1## wherein Z is C.sub.1 -C.sub.3 alkylamino, C.sub.1 -C.sub.3 alkylguanidino, C.sub.1 -C.sub.3 alkylamidino, or heterocycloalkyl and, M=H, a synthetically useful cation, or pharmaceutically acceptable cation. Such compounds as well as their pharmaceutically acceptable salts are useful as antibiotics. Also disclosed are processes for the preparation of such compounds; novel intermediates; pharmaceutical compositions comprising such compounds; and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: October 5, 1983
    Date of Patent: October 1, 1985
    Assignee: Merck & Co., Inc.
    Inventors: W. Alexander Andrus, Burton G. Christensen, James V. Heck
  • Patent number: 4543257
    Abstract: Disclosed are 1-carba-2-penem-3-carboxylic acids of the following structure: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, aryl, and aralkyl. Such compounds as well as their pharmaceutically acceptable salt, ester and amide derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: January 4, 1980
    Date of Patent: September 24, 1985
    Assignee: Merck & Co., Inc.
    Inventors: Lovji D. Cama, Burton G. Christensen
  • Patent number: 4534898
    Abstract: This invention relates to 1-oxa-1-dethia-cephalosporins which are useful as anti-biotics.
    Type: Grant
    Filed: July 20, 1983
    Date of Patent: August 13, 1985
    Assignee: Merck & Co., Inc.
    Inventors: Seiji Shibahara, Tsuneo Okonogi, Yasushi Murai, Shunzo Fukatsu, Tadashi Wakazawa, Taro Niida, Burton G. Christensen
  • Patent number: 4530841
    Abstract: Disclosed are 6- and 6,6-disubstituted-3-substituted amino-1-azabicyclo[3.2.0]hept-2-en-7-one-2-carboxylic acids (I): ##STR1## wherein R.sup.1 and R.sup.2 are, inter alia, independently selected from the group consisting of hydrogen, substituted and unsubstituted: alkyl, aryl, and aralkyl; and R' and R" are independently selected from the group consisting of: H, substituted and unsubstituted alkyl and aralkyl, or together form a substituted or unsubstituted cyclic group.Such compounds and their pharmaceutically acceptable salt, ester and amide derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: June 14, 1982
    Date of Patent: July 23, 1985
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe
  • Patent number: 4479947
    Abstract: The (5-R-2-oxo-1,3-dioxolen-4-yl)methyl moiety: ##STR1## wherein R is loweralkyl of 1-6 carbon atoms, especially methyl or t-butyl; when utilized as an ester on a pharmaceutical having a carboxylic acid functionality, enhances oral absorption of the pharmaceutical. This effect is applicable to a broad range of pharmaceutically active substances, including antibiotics, and antihypertensives as well as other classes of therapeutic agents.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: October 30, 1984
    Assignee: Merck & Co., Inc.
    Inventor: Burton G. Christensen
  • Patent number: 4465632
    Abstract: Disclosed are 1-, 6- and 2-substituted-1-carba-2-penem-3-carboxylic acids of the following structure: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, aryl, and aralkyl. Such compounds as well as their pharmaceutically acceptable salt, ester and amide derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: July 15, 1982
    Date of Patent: August 14, 1984
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, David H. Shih
  • Patent number: 4447602
    Abstract: A process is provided which yields derivatives of cephalosporins and penicillins. The process starts with 7-acylaminocephalosporin, or 6-acylaminopenicillin, then the latter compounds are treated with an organolithium compound, followed with t-butyl-hypochlorite. Finally, a defined reagent is added yielding a side chain on the carbon adjacent to the amino-nitrogen. Novel intermediate compounds are also described. The end compounds prepared are active against both gram-positive and gram-negative bacteria.
    Type: Grant
    Filed: June 3, 1977
    Date of Patent: May 8, 1984
    Assignee: Merck & Co., Inc.
    Inventors: Raymond A. Firestone, Lovji D. Cama, Burton G. Christensen
  • Patent number: 4424230
    Abstract: Disclosed are 6-(1'-hydroxyethyl)-3-substituted amino-1-azabicyclo?3.2.0!hept-2-en-7-one-2-carboxylic acids (I): ##STR1## wherein R' and R" are independently selected from H, substituted and unsubstituted alkyl and aralkyl groups, or together form a substituted or unsubstituted cyclic group. Such compounds and their O- and carboxyl derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: July 11, 1980
    Date of Patent: January 3, 1984
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe
  • Patent number: 4400323
    Abstract: In a process for the total synthesis of thienamycin from L-aspartic acid via intermediate III: ##STR1## there is disclosed a process for preparing III via ##STR2## wherein R is a protecting group.
    Type: Grant
    Filed: January 21, 1981
    Date of Patent: August 23, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe, Thomas N. Salzmann
  • Patent number: 4397861
    Abstract: Disclosed are N-acyl and carboxyl derivatives of the antibiotic thienamycin, which has the following structure: ##STR1## Such derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such derivatives, pharmaceutical compositions comprising such derivatives and methods of treatment comprising administering such derivatives and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: November 16, 1981
    Date of Patent: August 9, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, John Hannah, William J. Leanza, David H. Shih
  • Patent number: 4388310
    Abstract: Disclosed are 6-amido-2-S-oxides of substituted 2-organothio-pen-2-em-3-carboxylic acids (I) which are useful as antibiotics and as intermediates in the synthesis of substituted pen-2-em-3-carboxylic acids: ##STR1## wherein: R.sup.1 is H or acyl; R.sup.2 is hydrogen or methoxyl; R.sup.3 is alkyl having from 1-6 carbon atoms; phenylalkyl having 7-12 carbon atoms; and cycloalkyl having 3-6 carbon atoms; and R.sup.4 is hydrogen, a removable protecting group or a pharmaceutically acceptable salt or ester moiety.
    Type: Grant
    Filed: March 1, 1982
    Date of Patent: June 14, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Frank P. DiNinno, David A. Muthard, Ronald W. Ratcliffe
  • Patent number: 4386030
    Abstract: Disclosed are 6-(1'-hydroxyethyl)-2-substituted-pen-2-em-3-carboxylic acids of the following structure: ##STR1## wherein R is, inter alia, hydrogen, --OR, --SR, --NR.sub.2, alkyl, aryl, aralkyl, or heterocylcyl; n is 0 or 1; when n=1 R is as defined but not --SR. Such compounds and their pharmaceutically acceptable salt and ester derivatives are useful as antibiotics. Also disclosed are processes for the preparation of such compounds, pharmaceutical compositions comprising such compounds and methods of treatment comprising administering such compounds and compositions when an antibiotic effect is indicated.
    Type: Grant
    Filed: November 12, 1981
    Date of Patent: May 31, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Frank P. DiNinno
  • Patent number: 4383946
    Abstract: Disclosed is a process for the total synthesis of 1-carbapenem antibiotics (I) from L-aspartic acid via central intermediates II and III: ##STR1## wherein R is hydrogen, a pharmaceutically acceptable ester moiety or salt cation, or a readily removable blocking group; R.sup.6, R.sup.7 and R.sup.8 are, inter alia, independently selected from the group consisting of hydrogen, alkyl, alkenyl, aryl and aralkyl; R.sup.1' and R.sup.e are hydrogen, or a readily removable protecting group; R.sup.a, R.sup.b and R.sup.c are selected from alkyl, aryl or aralkyl.
    Type: Grant
    Filed: September 18, 1981
    Date of Patent: May 17, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe, Thomas N. Salzmann
  • Patent number: 4378315
    Abstract: Disclosed is a process for the total synthesis of thienamycin from L-aspartic acid via intermediate III: ##STR1## R=H, blocking group or salt cation.
    Type: Grant
    Filed: May 11, 1981
    Date of Patent: March 29, 1983
    Assignee: Merck & Co., Inc.
    Inventors: Burton G. Christensen, Ronald W. Ratcliffe, Thomas N. Salzmann