77744-45-7Relevant academic research and scientific papers
A unified synthesis of cyclic ethers or lactones via Pd-catalyzed intramolecular O-functionalization of sp3C[sbnd]H bonds
Wang, Haifeng,Niu, Youhong,Zhang, Guoying,Ye, Xin-Shan
supporting information, p. 4544 - 4548 (2016/09/23)
A general approach for the synthesis of lactones or cyclic ethers via Pd-catalyzed C(sp3)[sbnd]H activation and intramolecular C[sbnd]O functionalization starting from carboxylic acids or alcohols using the bidentate directing group has been de
Synthetic studies of carolacton: Enantioselective total synthesis of C1-C8 and C9-C19 fragments of the molecule
Rao, Kulakarnisripad,Ghosh, Subhash
, p. 2745 - 2751 (2013/10/22)
This paper describes synthetic studies towards carolacton, a highly potent antibiotic against dental caries and endocarditis related bacterium Streptococcus mutans. The synthesis of the 12-membered lactone with a diversely functionalized keto acid side chain was accomplished by utilizing a blend of chiral pool and aldol strategies. Carbon chain C1-C8 was derived by utilizing Paterson aldol methodology and a Corey-Fuchs reaction. The C9-C19 chain was prepared by means of iterative Evans asymmetric alkylations and an E-selective cross-metathesis reaction. Georg Thieme Verlag Stuttgart New York.
12 MEMBERED-RING MACROLACTAM DERIVATIVES
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, (2009/01/24)
There provided a 12-membered-ring macrolactam derivative having antitumor activity: A compound represented by Formula (1) or a salt thereof. In this Formula, R1 is a hydrogen atom, a C1-6 alkyl group, a C1-6 alkylcarbonyl
Bridging of macrodithionolactones to bicyclic systems. Synthesis and modeling of oxapolycyclic frameworks
Nicolaou,Hwang,Marron,DeFrees,Couladouros,Abe,Carroll,Snyder
, p. 3040 - 3054 (2007/10/02)
A new reaction involving bridging of macrodithionolactones to bicyclic systems is described. A series of macrodiolides was prepared and converted to the requisite macrodithionolactones. The latter substrates were induced to undergo bridging across the macrocyclic ring by exposure to sodium naphthalenide, leading to stable bicyclic systems upon addition of methyl iodide. The mixed thioketals so obtained were converted to a number of saturated or unsaturated bicyclic or polycyclic systems by removal of the sulfurs. The stereochemistry of bridging follows the relative energy of the cis and trans products rather than the conformational preferences of the macrocycles. This is confirmed by MM2 calculations and X-ray crystal structure determinations. The unusual stereochemical course of some of the reported reactions, elucidated by X-ray, has been given a mechanistic basis by conformation searching coupled by energy evaluation by MM2 and PRDDO. Several new sets of MM2 parameters were evolved during this work.
Template-Driven Macrolide Closures.
Rastetter, William H.,Phillion, Dennis P.
, p. 3209 - 3214 (2007/10/02)
Thiol-functionalized crown ethers serve as reagents for macrolide closures.The thioesters derived from these crown ethers and ω-hydroxy carboxylic acids yield macrolides when treated with potassium tert-butoxide.The cyclization reaction proceeds via a templated conformation in which the ω-alkoxide is held proximate to the thioester through ionic bonding to the crown-bound potassium cation.Variations in crown ether structure in the series 1-4 show that the criterion of proximate binding is necessary but not sufficient to ensure efficient macrolide closure.The optimal crown ether reagent is thought to provide transition-state stabilization for the attack of the alkoxide on the thioester carbonyl by situating the carbonyl oxygen immediately adjacent to the crown-bound potassium cation.
