Patents by Inventor Alexandra E. Graham

Alexandra E. Graham 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).

  • Hypophosphite deoxygenation reactions in the synthesis of erythromycin derivatives
    Patent number: 6040440
    Abstract: A process for the preparation of 4"-deoxyerythromycins, having the formula: ##STR1## wherein R is H or OH, R.sup.1 is H or loweralkyl, and R.sup.2 is H or CH.sub.3 by treatment of the starting material, 2'-O-acetyl-4"-imidazolylthiocarbamoyl-erythromycin, with a hypophosphite reagent, in a water-miscible protic solvent optionally comprising a phase transfer agent. In a preferred embodiment, the water-miscible solvent is an alcohol and the starting material is reacted with sodium hypophosphite, ACVA and tetra-n-butylammonium hydroxide.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: March 21, 2000
    Assignee: Abbott Laboratories
    Inventors: Alexandra E. Graham, Albert V. Thomas, Rachel R. P. Yang
  • Process for preparation of 4"-deoxyerythromycins A and B
    Patent number: 5760198
    Abstract: A process for the preparation of 4"-deoxyerythromycins, having the formula: ##STR1## wherein R is H or OH, and R.sup.1 is H or loweralkyl by treatment of the 2'-O-acetyl-4"-imidazolylthionocarbonyl-erythromycin starting material with the radical initiator 4,4'-azobis-(4-cyanovaleric acid), H.sub.3 PO.sub.2 and an organic base in a water-miscible solvent and optionally eliminating the 2'-O-acetyl group. In a preferred embodiment, the water-miscible solvent is an alcohol and the deoxygenation and deacetylation is carried out in one step.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: June 2, 1998
    Assignee: Abbott Laboratories
    Inventors: Shyamal I. Parekh, Alexandra E. Graham, Michael John Dipierro, Albert V. Thomas, David A. Riley