Camptothecin, 20-deoxy

N. Shibata, T. Ishimaru, M. Nakamura, T. Torn, 20-Deoxy-20-fluorocamptothecin Design and synthesis of Camptothecin isostere, Synlett (2004) 2509-2512. 

Binding selectivities can be increased by polar interactions, e.g., Coulomb interactions or hydrogen bonds, between functional groups of CD derivatives and functional groups at the guest. Recently, we demonstrated the superior binding properties of hepta-6-5-6-deoxy- i-CD derivatives towards the cancer treatment dmg camptothecin [47],... 

Lown JW, Chen HH 1980 Studies related to antitumor antibiotics. XIX. Studies on the effects of the antitumor agent camptothecin and derivatives on deoxy-ribonucleic acid. M Biochem Pharmacol 29 905-915... 

Alternatively, 20-deoxy-20-fluorocamptothecin could be prepared from camptothecin or a synthetic intermediate by stereospecific displacement of the hydroxyl group with DAST. °° The cytotoxicity study showed that the (/ )-enantiomer of 20-fluorocamptothecin is essentially inactive, while the (5)-enantiomer is at least 100—1000 times less potent than the natural product. Unfortunately, in this case, the substitution of the hydroxy group by a fluorine atom has a significant detrimental effect on interactions of the drug with the topoisomerase I/DNA complex. 

Shibata N, Ishimaru T, Nakamura M, Toru T. 20-Deoxy-20-fluorocamptothecin design and synthesis of camptothecin isostere. Synlett 2004 2509-2512. 

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