ORGN 468 |
| Won Jun Choi1, Hyung Ryong Moon2, Byul Nae Yoo1, Dae Hong Shin1, Kang Man Lee1, and Lak Shin Jeong1. (1) Laboratory of Medicinal Chemistry, College of Pharmacy, Ewha Womans University, 11-1 Seodaemun-ku, Daehyun-dong, Seoul, South Korea, (2) College of Pharmacy, Pusan National University, Pusan, 609-735, South Korea |
| Although many synthetic methods to the carbocyclic nucleosides have been reported so far, they sometimes suffered from inconsistent and low overall yields, lengthy steps, racemization, lack of large-scale preparations, and so on. Thus, a short and efficient procedure to the carbocyclic sugar has highly been demanded. Recently, several groups including our laboratory have published short and efficient syntheses of D- and L-cyclopentenone derivatives without 4-hydroxymethyl side chain which can be served as the versatile intermediates for the synthesis of D- and L-carbocyclic nucleosides, but introduction of the 4-hydroxymethyl group to D- and L-cyclopentenone derivatives was inconsistent, despite of the reported procedure. Thus, we are very interested in developing a new and efficient synthetic route to the D-cyclopentenone derivative with 4-hydroxymethyl side chain for the extensive modification of the cyclopentenyl sugar moiety. We have completed very short, efficient and preparative synthesis of the target compound with various protective groups, starting from D-ribose in 7 steps and 45-50% overall yields (> 20 g scale). Our method is highlighted by the 100% stereoselective formation of the tertiary allylic alcohol enforced by the bulkiness of the protective group and oxidative rearrangement of the tertiary allylic alcohol under mild conditions. To our best knowledge, our synthetic method can be regarded as the best procedure from the standpoint view of number of steps, overall yields, large-scale preparation, and mild reaction conditions and has a great potential to be utilized extensively in the SAR study of the carbocyclic nucleosides. |
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Total Synthesis, Asymmetric Reactions and Syntheses, Bioorganic
9:00 AM-11:00 AM, Wednesday, March 31, 2004 Anaheim Convention Center -- Hall C, Poster
Division of Organic Chemistry |