112953-21-6Relevant articles and documents
The Regioselectivity of Cycloaddition Reactions Between Diazomethane and 3-Vinylcephalosporins
Fell, Stephen C. M.,Pearson, Michael J.,Burton, George,Bateson, John H.
, p. 1361 - 1364 (2007/10/02)
Diphenylmethyl (6R,7R)-7-phenylacetamido-3-vinylceph-3-em-4-carboxylate 1 undergoes regioselective addition of diazomethane to give the 1-pyrazoline 7, which readily undergoes thermolysis of give the cyclopropyl analogue 10.The regioselectivity is reversed, however, when one or more electron withdrawing ester substituents are attached to the 3-vinyl group.