
TY  - JOUR
A1  - Davis, M 
A1  - Wu, WY 
T1  - A New Preparative Route to 3-Unsubstituted Cephalosporins From Penicillin V
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1988
VL  - 41
IS  - 10
SP  - 1591
EP  - 1600
KW  - 
UR  - https://doi.org/10.1071/CH9881591 
N2  - p- Nitrobenzyl (2R,3R)-2-(benzothiazol-2&#8242;-yldithio)-&#945;-isopropylidene-4- oxo-3-phenoxyacetyl-aminoazetidine-1-acetate (7), readily prepared from penicillin V, can be converted into the corresponding 2-allylthio compound (2) by addition of allyl bromide and sodium borohydride at a low temperature. This compound (2) on treatment with ozone, followed by cyclization with trimethyl  phosphite, produces a 3H-ceph-3-em ester (4). The ester can be easily de-esterified to the free acid (1b). 
ER  -

