This invention provides a novel compound of the formula: ##STR1## wherein X is L-HyPro or L-Pro, R is --CH.sub.3 or --CH(CH.sub.3).sub.2, and n is an integer from 9 to 12, or its salt, a process for producing the compound which comprises cultivating a microorganism which belongs to the genus Pseudomonas and produces the compound in a medium and recovering the compound from the medium and a biologically pure culture of Pseudomas sp. PB-6250 producing the compound.