Patents by Inventor Etsumi Nakamura

Etsumi Nakamura 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).

  • Purification of penicillin derivative
    Patent number: 4313875
    Abstract: Crude 6-[D-2-(D-2-amino-3-N-methylcarbamoyl-propionamido)-2-p-hydroxyphenylaceta mido]penicillanic acid can be purified by the steps of:(A) contacting an aqueous solution of 6-[D-2-(D-2-amino-3-N-methylcarbamoyl-propionamido)-2-p-hydroxyphenylaceta mido]-penicillanic acid with a nonpolar, macroporous styrenedivinylbenzyl copolymer adsorption resin to adsorb 6-[D-2-(D-2-amino-3-N-methylcarbamoyl-propionamido)-2-p-hydroxyphenylaceta mido]penicillanic acid on the resin,(B) eluting the adsorbed 6-[D-2-(D-2-amino-3-N-methylcarbamoyl-propionamido)-2-p-hydroxyphenylaceta mido]penicillanic acid with water or a mixture of water and a water-miscible organic solvent,and then(C) isolating pure 6-[D-2-(D-2-amino-3-N-methylcarbamoyl-propionamido)-2-p-hydroxyphenylaceta mido]penicillanic acid from the eluates.
    Type: Grant
    Filed: August 27, 1980
    Date of Patent: February 2, 1982
    Assignee: Tanabe Seiyaku Co., Ltd.
    Inventors: Etsumi Nakamura, Takashi Suzuki, Tadasu Yanagida, Minehiko Yamamura