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US 4,051,131 AGranted
Intermediates for preparing cephalosporins
AssigneeAmerican Home Products Corporation (Del.)
InventorCharles A. Robinson
Life of this patent
Estimating the term…
Abstract
.DELTA..sup.3 -Cephalosporins are prepared by reacting novel diorganodihalosilane or monorganodihalosilane derivatives of 7-aminocephalosporanic acid ("7ACA") and 7-amino-desacetoxycephalosporanic acid ("7ADCA") with known acylating agents followed by hydrolysis or alcoholysis to produce .DELTA..sup.3 -cephalosporins with useful antibiotic activity. The dialkyldihalosilane derivatives are prepared by adding a base such as triethylamine slowly to a mixture of 7ACA or 7ADCA and a dialkyldihalosilane.
Claims7
A compound of the group consisting of those having the following formula:
- ##STR12## wherein:
- R.sup.1 is of the group consisting of hydrogen, lower alkyl, phenyl, loweralkylphenyl and benzyl
- R.sup.2 is of the group consisting of lower alkyl, phenyl, loweralkylphenyl and benzyl
- R.sup.3 is hydrogen or ##STR13## R.sup.a is of the group consisting of tetrazolylacetyl and sydnonylacetyl;
- W is of the group consisting of hydrogen and ##STR14## wherein R.sup.1 and R.sup.2 have the same meaning as before, and X is halogen;
- m and p are integers from 0 to 1 and are always equal
- n is an integer from 1 to about 25;
- Y is of the group consisting of halogen, and groups of the following formula:
- ##STR15## wherein R.sup.a has the same meaning as before;
- with the provisos that, in Formula I,
- 1. when m is o and p is 0, n is more than 1;
- 2. when n is more than 1, the moieties A of the additional groups B recur in random head-toward-head, head-toward-tail and tail-toward-tail disposition;
- 3. when W is hydrogen, n is 1, and Y in Formula III, then R.sup.a is hydrogen,
- 4. when W is hydrogen or ##STR16##
11 more elements
Dependencies are inferred from the claim text.