EXHIBIT 4.7 WARRANT AGREEMENT FOR "CLASS B WARRANTS" AGREEMENT (this "Agreement") dated as of August 9, 1996, by and between XYTRONYX, INC., a Delaware corporation (the "Company") and AMERICAN STOCK TRANSFER & TRUST COMPANY, as warrant agent (the...Warrant Agreement • June 24th, 1997 • Xytronyx Inc • In vitro & in vivo diagnostic substances • New York
