Asymmetric Total Synthesis of Salinosporamide A, D and I

학위논문(석사) -- 서울대학교대학원 : 약학대학 약학과, 2024. 2. 김상희.Salinosporamide 계열 천연물은 해양 미생물인 Salinispora에 서 추출된 천연물로, γ-lactam-β-lactone의 bicyclic core 구조를 갖는다. 우리는 D-serine을 유일한 chiral source로 이용하여 (-)-salinosporamide D와 I의 첫 번째 비대칭적 전합성을 완료하 였다. Serine으로부터 유도된 oxazolidine의 알돌 반응에서 memory of chirality와 dynamic kinetic resolution의 개념을 이용 한 최적의 반응 조건을 탐색하였고, 높은 diastereoselectivity와 enantioselectivity를 보여주었다. 이를 통해 pyrrolidinone core의 3개의 연속적인 탄소에 원하는 stereocenter를 선택적으로 빠르게 구축하는 것에 성공하였으며, pyrrolidinone 중간체로부터 barbier type allylation으로 2개의 추가적인 stereocenter를 도입하였다. 이로써 known compound로부터 salinosporamide D는 11단계, salinosporamide A와 I는 13단계만에 합성을 완료하였다.Salinosporamids are natural products that extracted from the marine microorganism, Salinispora tropica, and have a bicyclic core structure of γ-lactam-β-lactone. We completed the first asymmetric total synthesis of (-)-salinosporamide D and I using D-serine as the sole chiral source. In the aldol reaction of oxazolidine derived from D-serine, optimal reaction conditions were explored using the concepts of memory of chirality and dynamic kinetic resolution. high diastereoselectivity and enantioselectivity were also shown. Through this, we succeeded in quickly and selectively constructing the desired stereocenters on three contiguous carbons of the pyrrolidinone core, and two additional stereocenters were introduced through Barbier-type allylation. As a result, the synthesis of salinosporamide D from a known compound was completed in 11 steps, and salinosporamide A and I were synthesized in 13 steps.I. Introduction 3 II. Results and Discussion · 5 III. Conclusion · 12 IV. Experimental Section 13 V. HPLC data 49 VI. 1H, NMR, 13C NMR, NOESY data 52 VII. References 77 VIII. Abstract in English 79석

Effects of socioeconomic position and school characteristics on adolescent suicidal ideation

학위논문 (석사)-- 서울대학교 대학원 : 보건학과(보건정책관리학전공), 2011.2. 양봉민.Maste

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