tetralactams with two dimethyleneoxy moieties is described. The method consists in the ring closure of a bis-secondary amine with a diamide diacid activated by the thiazolidine-2-thione group. The cyclization does not require high dilution techniques and provides the expected tetralactams in good yields, ranging from 42% to 73%. This synthetic pathway leads to dissymmetrical or symmetrical molecules with
Efficient One-Pot Synthesis of Doxorubicin Conjugates Through Its Amino Group to Melanotransferrin P97
作者:Qingqi Chen、Damian A. Sowa、Jianlin Cai、Reinhard Gabathuler
DOI:10.1081/scc-120021829
日期:2003.1.8
The amino group of doxorubicin I is reacted with bis-NHS-ester linkers 6, or anhydrides 13 to offer in high yield modified doxorubicins 7-12 and 14-16, respectively. Compounds 7-12 are mono-NHS-esters, and can be directly coupled with melanotransferrin (p97), a useful vector with the ability to cross the blood-brain barrier, to yield the expected doxorubicin-p97 conjugates. Upon activating the carboxylic group with BTTU, compound 14-16 could be used in the same reaction. Structurally, the amino group of doxorubicin is covalently bonded to the amino groups of p97. The conjugates are potential candidates for treatment of brain tumors.