-N- syn-27-stimulation of cell-mediated immunity.'This unique compound is one of a series of structurally related 1-(ary1amino)-1H-pyrrol-l-amines and 4-(1H-pyrrol-l-yl-imino)-2, 5-~ yclohexadienes that were investigated for in vitro antibacterial activity and in vivo antitubercular activity. The purpose of this paper is to describe the syn-thesis of this series of compounds and to relate some of the structural requirements necessary for their ...