Patents by Inventor Keith M. Ramig

Keith M. Ramig 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).

  • Process for the preparation of (R)-3-hexyl-5,6-dihydro-4-hydroxy-6-undecyl-2H-pyran-2-one and (R)-5,6-dihydro-6-undecyl-2H-pyran-2,4 (3H)-dione
    Patent number: 5420305
    Abstract: A process for the preparation of a tautomeric mixture of compounds of the formulas ##STR1## wherein W is hydrogen or C.sub.6 H.sub.13, which comprises treating a compound of the formula ##STR2## wherein R is unsubstituted or substituted alkoxy, arylalkoxy, aryloxy or amine and R.sup.1 is hydrogen or when R is alkoxy, substituted alkoxy, substituted amine, unsubstituted or substituted arylalkoxy R.sup.1 can also be metal, with a compound of the formula ##STR3## wherein W is as described above, both X and Y are reducible groups or X is hydrogen and Y is a reducible group or Y is hydrogen and X is a reducible group and, Z is hydroxy or a leaving group to form the compound of formula IV ##STR4## wherein W, X, Y and R are as defined above, the compound of formula IV is treated with a low valent metal to form a tautomeric mixture of compounds of formulas I and Ia, which are useful in the synthesis of tetrahydrolipstatin.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: May 30, 1995
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Keith M. Ramig, John J. Landi, Jr.
  • Process for the preparation of (R)-3-hexyl-5,6-dihydro-4-hydroxy-6-undecyl-2H-pyran-2-one and (R)-5,6-dihydro-6-undecyl-2H-pyran-2,4(3H)-dione
    Patent number: 5274143
    Abstract: A process for the preparation of a tautomeric mixture of compounds of the formulas ##STR1## wherein W is hydrogen or C.sub.6 H.sub.13, which comprises treating a compound of the formula ##STR2## wherein R is unsubstituted or substituted alkoxy, arylalkoxy, aryloxy or amine and R.sup.1 is hydrogen or when R is alkoxy, substituted alkoxy, substituted amine, unsubstituted or substituted arylalkoxy R.sup.1 can also be metal, with a compound of the formula ##STR3## wherein W is as described above, both X and Y are reducible groups or X is hydrogen and Y is a reducible group or Y is hydrogen and X is a reducible group and, Z is hydroxy or a leaving group to form the compound of formula IV ##STR4## wherein W, X, Y and R are as defined above, the compound of formula IV is treated with a low valent metal to form a tautomeric mixture of compounds of formulas I and Ia, which are useful in the synthesis of tetrahydrolipstatin.
    Type: Grant
    Filed: March 12, 1992
    Date of Patent: December 28, 1993
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Keith M. Ramig, John J. Landi, Jr.