摘要 |
<p>Novel nitrosourea derivatives are provided which possess a high level of inhibitory activity against leukemia and tumors and which are therefore useful for pharmaceutical purposes. The compounds have the structure represented by formula (I): <IMAGE> (I) wherein R0 represents -OH or -OCmH2m+1 where m is an integer of 1 to 3 and one of R1, R2, R3 and R4 represents <IMAGE> where X is <IMAGE> or an alkylene group of 1 to 3 carbon atoms, n is an integer of 1 to 3 and Y is the group on the alpha -carbon atom of an alpha -amino acid and each of the remaining three represents -OH; or wherein R0 represents <IMAGE> and R1, R2, R3 and R4 each represent -OH; or by formula (II): <IMAGE> (II) wherein X and n have the same meanings as above; and p is an integer of 1 to 5.</p> |