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US 4,792,598 AGranted
Poly-dicaboxylic acid anhydrides and polymeric anhydrides therefrom
AssigneeSandoz Ltd.
InventorGerd Ziegast
Life of this patent
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Abstract
New poly-dicarboxylic acid anhydrides, which are suitable as bio-degradable matrix materials for the controlled release of medicinal agents in humans. The anhydrides have the following formula: ##STR1## where ##STR2## where n=an integer of two or more, for the first three radicals, or one or more for the fourth.
Claims13
A poly-dicarboxylic acid anhydride, containing structural units of formula ##STR157## wherein A represents a direct bond or A represents (C.sub.1-12)alkylene in the ortho-, meta- or para-position in the phenylring, and wherein
- B represents B1 or B2 where b.sub.1 is --CH.sub.2 --CH.sub.2 --O-- with n>2, --CH.sub.2 --CH.sub.2 --CH.sub.2 --O-- or ##STR158## with n.gtoreq.2, and B.sub.2 is ##STR159## with n=1 and wherein m=1, 2, 3 or 4 and wherein R is (C.sub.1-20)alkyl or substituted phenyl, or wherein ##STR160## is a (co)(poly)ester group of one or more identical or different hydroxy carboxylic acid units, and
- D=H, CH.sub.3 or OCH.sub.3 in the ortho-, meta- or para-position in the phenylring,
- with a molecular weight of 2,000 to 140,000 and with the units of formula I in homo- or copolymeric arrangement the polymer having terminal monocarboxylic acid anhydride residues or free carboxylic acid groups.
Dependencies are inferred from the claim text.