Reaktion #2243

Reaktionsgleichung

DDQ

rapamycin

water

→

desired product

7-Demethoxy-7-Oxorapamycin

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe mixture was filtered through celite
2. 2
   Sonstigepartitioned between dichloromethane and brine
3. 3
   Trocknenthe organic extracts were dried over anhydrous magnesium sulfate
4. 4
   Sonstigethe resulting crude material was purified by prep TLC

Vorschrift

To a solution of rapamycin (5 mg, 0.055 mmol) in dichloromethane (0.1 mL) was added water (0.02 mL) followed by DDQ (2.4 mg, 0.011 mmol), and the resulting dark brown suspension was stirred at room temperature for 45 min. The mixture was filtered through celite and then partitioned between dichloromethane and brine; the organic extracts were dried over anhydrous magnesium sulfate and the resulting crude material was purified by prep TLC. The desired product was isolated as a colorless oil (1.2 mg). 1 H NMR (CDCl3, 400 MHz, 3:1 mixture of trans:cis amide rotamers; data for the trans-rotamer): -- 7.145 (d, J=10.4 Hz, 1H), 6.635 (dd, J=14.9, 10.6 Hz, 1H), 6.57-6.48 (m, 2H), 6.224 (dd, J=15.1, 10.6 Hz, 1H), 5.662 (dd, J=15.1, 8.6 Hz, 1H), 5.447 (d, J=11.2 Hz, 1H), 4.305 (br d, J=5.4 Hz, 1H), 3.983 (d, J=5.4 Hz, 1H), 3.385 (s, 3H), 3.346 (s, 3H),; MS (ESl+/NH4OAc) m/z 920 (M+Na+), 915 (M+NH4+), 898, 880; UV (MeOH) max 318 nm.

Quelle