Your team is studying the problem of an intramolecular ring closure of enediyne systems

Chapter 13, Problem 58

(choose chapter or problem)

Your team is studying the problem of an intramolecular ring closure of enediyne systems importantin the total synthesis of dynemicin A, which exhibits potent antitumor activity.HOH%BBAAAA BBAAAAO HNOH O OHOHCOOHOCH3CH3Dynemicin A~ %%One research group tried the following approaches to effect this process. Unfortunately, all wereunsuccessful. Divide the schemes among yourselves and assign structures to compounds A through D.(Note: R9 and R0 are protecting groups.)1. NBAAAAOOCH3CH3O%CH3OHOCH3OCH3HCH3SO2Cl,(CH3CH2)3NALiNR2~NBAAAAOOCH3CH3O%CH3OCH3OCH3%H??2. B RN1. (CH3CH2CH2CH2)4NF,THF (removes R)2. CH3SO2Cl,(CH3CH2)3NAAAAOCH3%CH3OHO~ RNAAAAOCH3%CH3OHR~% %ROCH3OCH3?OCH3OCH3?CLiNR2% RNAAAAOCH3%CH3HHO~%OCH3OCH3?3. RNAOCH3%CH3OHBrODOHMild base}%% LiNR2% RNAAAAOCH3%CH3HHO~%HChapter 13 607A successful model study (shown here) provided an alternative strategy toward the completion of thetotal synthesis.CHOO OLDAOH