| 摘要 |
derivs. of formula (I) are new: (R1 is lower mono- or polyhydroxyalkyl: R2 is H, lower alkyl or R1; each R3 is independently H or lower alkyl; X is an alkylene gp. interrupted by one or more sulphur or selenium atoms and opt. interrupted by O, di(lower alkyl)silyl or tetra(lower alkyl)disiloxane).. Cpds. (I) are X-ray contrast agents which can be used as aq. solns. for direct or indirect lymphography. They have good stability, are free of embolic side-effects, and have excretion times of less than 24 hr. |
