Abstract
The surface anesthetic activities of ten bufadienolides, i. e., resibufogenin, bufalin, bufotalin, desacetyl-bufotalin, cinobufagin, desacetyl-cinobufagin, cinobufotalin, desacetyl-cinobufotalin, telocinobufagin and marinobufagin, were studied using the guinea pig cornea. With exceptions of resibufogenin and marinobufagin, all substances tested were more effective than cocaine. Their anesthetic activities were in the following order : bufalin > telocinobufagin > bufotalin > cinobufagin > cinobufotalin > desacetyl-bufotalin ≨ desacetyl-cinobufagin ≨ desacetyl-cinobufotalin. Resibufogenin and marinobufagin had no appreciable effect on the cornea. There is some correlation between the chemical structure and the surface anesthetic activity in the bufadienolides tested.
