國立高雄大學圖資館 |

語系: 繁體中文

說明(常見問題)

圖資館首頁

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Applications of samarium(II) iodide-...

George, Kelly M.

Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin.
作者:	George, Kelly M.
面頁冊數:	344 p.
附註:	Source: Dissertation Abstracts International, Volume: 66-06, Section: B, page: 3134.
附註:	Supervisor: Gary A. Molander.
Contained By:	Dissertation Abstracts International66-06B.
標題:	Chemistry, Organic.
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3179736
ISBN:	0542198797

Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin.
George, Kelly M.

Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin. - 344 p.

Source: Dissertation Abstracts International, Volume: 66-06, Section: B, page: 3134.

Thesis (Ph.D.)--University of Pennsylvania, 2005.

(+)-Isoschizandrin is one of nearly forty dibenzocyclooctadiene lignans isolated from the fruit of Schizandra chinensis. The extract from this lignan-rich plant finds use in traditional medicine as an antitussive and also displays anti-ulcer activity in rats. Synthesis of the eight-membered ring of (+)-isoschizandrin, possessing the attendant functionality and stereochemistry, provides a significant synthetic challenge. The 13-step synthesis of (+)-isoschizandrin reported herein features a novel samarium(II) iodide-promoted 8-endo ketyl-olefin coupling to assemble the eight-membered ring present in the target concomitantly with the required functionality and stereochemistry.

ISBN: 0542198797Subjects--Topical Terms:

193634
Chemistry, Organic.

Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin.
LDR:03258nmm _2200289 _450 001 167420
005 20061005085932.5
008 090528s2005 eng d
020 $a 0542198797
035 $a 00198036
040 $a UnM $c UnM
100 0 $a George, Kelly M. $3 237568
245 1 0 $a Applications of samarium(II) iodide-promoted 8-membered ring cyclization reactions in natural product total synthesis: I. The total synthesis of (+)-isoschizandrin. II. Progress toward the total synthesis of variecolin.
300 $a 344 p.
500 $a Source: Dissertation Abstracts International, Volume: 66-06, Section: B, page: 3134.
500 $a Supervisor: Gary A. Molander.
502 $a Thesis (Ph.D.)--University of Pennsylvania, 2005.
520 # $a (+)-Isoschizandrin is one of nearly forty dibenzocyclooctadiene lignans isolated from the fruit of Schizandra chinensis. The extract from this lignan-rich plant finds use in traditional medicine as an antitussive and also displays anti-ulcer activity in rats. Synthesis of the eight-membered ring of (+)-isoschizandrin, possessing the attendant functionality and stereochemistry, provides a significant synthetic challenge. The 13-step synthesis of (+)-isoschizandrin reported herein features a novel samarium(II) iodide-promoted 8-endo ketyl-olefin coupling to assemble the eight-membered ring present in the target concomitantly with the required functionality and stereochemistry.
520 # $a Over the last 25 years, samarium(II) iodide has been employed as a versatile reagent to effect a wide array of functional group transformations. Consequently, SmI2 has been applied in a large number of total synthetic efforts with great success. The construction of a variety of different ring systems can be achieved by exploiting the mild and selective nature of SmI2. Specifically, SmI2 is capable of effecting medium-membered ring cyclizations, which have posed a significant challenge to chemists in the past. The results reported herein highlight the power of samarium(II) iodide to assemble the eight-membered rings present in the natural products (+)-isoschizandrin and variecolin.
520 # $a The goal of our research is to utilize a samarium(II) iodide-promoted annulation procedure for the construction of the cyclooctanyl core. Synthesis of the key hemiketal has been obtained in a model system. The success of this key reaction further demonstrates the utility of samarium(II) iodide to generate medium-sized rings in complex systems.
520 # $a The sesterterpenoid variecolin was first isolated by Hensens in 1991 from the fermentation of the fungus Aspergillus variecolor. Variecolin is an antagonist of the angiotensin-II AT1 receptor and has been shown to be a potent immunosuppressant. Despite such interesting properties, variecolin has received little synthetic attention, and so it is an active target for total synthesis in our laboratories.
590 $a School code: 0175.
650 # 0 $a Chemistry, Organic. $3 193634
690 $a 0490
710 0 # $a University of Pennsylvania. $3 212781
773 0 # $g 66-06B. $t Dissertation Abstracts International
790 $a 0175
790 1 0 $a Molander, Gary A., $e advisor
791 $a Ph.D.
792 $a 2005
856 4 0 $u http://libsw.nuk.edu.tw:81/login?url=http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3179736 $z http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3179736