Disclosed herein is a compound of Formula (I) having the following structure for activating T cells, promoting T cell proliferation, and/or exhibiting antitumor activity, a method of using the compounds disclosed herein for treating cancer, and a pharmaceutical composition comprising the same.

##STR00001##

Disclosed herein is a compound of Formula (I) having the following structure for activating T cells, promoting T cell proliferation, and/or exhibiting antitumor activity, a method of using the compounds disclosed herein for treating cancer, and a pharmaceutical composition comprising the same.

##STR00001##