eribulin [ B 1793,B 1939,B-1793,B-1939,E 7389,E-7389,ER 086526,ER-086526,ER-86526,ER086526,Eisai brand of eribulin mesylate,Halaven,NSC 707389,NSC-707389,NSC707389,eribulin mesylate ] a halichondrin B derivative that suppresses microtubule growth and acts as an antimitotic agent; structure in first source