THE INFLUENCE OF THE LIPOPHILICITY OF 7-OXOACYL-L-ALANYL-D-ISOGLUTAMINES ON THEIR IMMUNORESTORATION ACTIVITY IN-VIVO

In search for immunologically active dipeptides, a series of new N-(7- oxoacyl)-L-alanyl-D-isoglutamines has been synthesized where lipophili city was varied by changing the 7-oxoacyl residue from 7-oxooctanoyl t o 7-oxotetradecanoyl. The immunological properties of the compounds we re examined in an in vivo immunorestoration test. It was found that li pophilicity had a significant influence on the potency of the compound s tested. Compounds between N-(7-oxodecanoyl)-L-alanyl-D-isoglutamine and N-(7-oxotetradecanoyl)-L-alanyl-D-isoglutamine showed biphasic inf luence on efficacy. The most active compound found was 7-oxododecanoyl -L-alanyl-D-isoglutamine, which also has an activity comparable to tha t of azimexone.