April 28, 195)

Dr, J. Dubnoff

Blology Laboratories

Calif. Institute of Technology
Pasadena ),

California

Dear Dr. Dubnoff:

In response to your request of the 19th, I can furnish only
the very limited sample of ONPG that is attached to this letter,
As you know, the compound is not yet commercially available. If
you do have occasion to synthesise a larger batch, I would even
appreciate the exchange of a similar sample,

By "activation" <o you refer to the effect of benzene and
other lytic agente that I mentioned in my 1951 paper? If so, you
will probably be interested to communicate with Dr, Borie Rotman
at the Enzyme Institute here, for he has been studying this prob-
lem for the last several months,

Please let me know if I can be of any further service.

Yours sincerely,

Joshua Lederberg,
Associate Professor of Genet‘ es