Spergualin is an antibiotic found by Umezawa (one of the present inventors) et. al. (U.S. Pat. No. 4,416,899). Since its discovery, many Spergualin-related compounds have been synthesized by Umezawa et. al. (U.S. Pat. No. 4,529,549, U.S. Pat. No. 4,556,735, etc.).
The compounds of the present invention have an immuno-modulating action with low toxicity and are expected as a medicine.
Conventional immuno-modulating agent generally have a strong side effect. Therefore, a compound having an excellent immuno-modulating action with reduced side effect and toxicity has been desired.