1015-55-0Relevant articles and documents
A Radical-Based Synthesis of Lingzhiol
Mehl, Lea-Marina,Maier, Martin E.
, p. 9844 - 9850 (2017)
The polycyclic natural product lingzhiol [(±)-1] was synthesized from dimethoxytetralone 8 via cyclization of an intermediate benzylic radical, generated from spiroepoxide 14, onto an alkynyl substituent generating tetracyclic compound 13 with an exocyclic double bond. After oxidative cleavage of the double bond of 13 and reduction of the keto function of 23, the correct diastereomer, 12-syn, was converted to lingzhiol (1) via known steps. In a similar manner, lingzhiol analogue 39 was synthesized from 5-methoxy-1-tetralone (27).
Shimizu et al.
, p. 1772,1774, 1775 (1973)
Steric and Inductive Effects on the Hydrolysis of Quinone Bisketals
Chen, Chung-Pin,Swenton, John S.
, p. 4569 - 4576 (1985)
The effects of allylic substituents on the regiochemistry of monohydrolysis of tetralin-type quinone bisketals 12 have been studied.The requisite bisketals were prepared by anodic oxidation of the corresponding 1-substituted 5,8-dimethoxytetralin.Product studies establish that hydroxyl and ether functions at the allylic position preferentially afford quinone monoketals of type 13 wherein the ketal function nearest to the allylic substituent is hydrolyzed.The fluoro system also preferentially forms the monoketal 13 (R = F).A series of alkyl substituents were also studied, and increasing the size of the group led to increasing regioselectivity in favor of 13.Only the Δ1,2-unsaturated systems 12j,k preferentially gave monoketals in which the more distant ketal function had hydrolyzed.Kinetic studies established at least two major factors in the regiochemistry of the bisketal hydrolysis.While both the oxygenated and alkylated substituents gave monoketals 13 in which hydrolysis had selectively occurred at the nearer ketal function, the origins of the observed regioselectivity are different.Oxygenated systems gave the observed regiochemistry due to a rate retardation of the hydrolysis of the more distant ketal by what is proposed to be an inductive effect.However, alkyl substituents exerted their effect by increasing the rate of hydrolysis of the nearer ketal function due to a relief of strain energy.
Asymmetric synthesis and antitumor activity of cycloalkanin
Wu, Xihan,Xu, Liang,Cai, Junchao
, p. 2635 - 2638 (1999)
Cycloalkanin was accessible by a practical and efficient asymmetric synthesis. The chiral center of the target is introduced via an asymmetric C-arylation of chiral aldehyde in high de. The synthesized cycloalkanin was shown to be significantly active against P388 cell line as assayed by in vitro MTT method.
Synthesis of Methoxy-2-hydroxy-1,4-naphthoquinones and Reaction of One Isomer with Aldehydes under Basic Conditions
Ameer, Farouk,Giles, Robin G. F.,Green, Ivan R.,Pearce, Rene
, p. 1247 - 1258 (2007/10/03)
Two protocols for the synthesis of methoxy-2-hydroxy-1,4-naphthoquinones were investigated in order to evaluate their behavior towards aldehydes under amine-basic conditions. Both the nature of the quinone and aliphatic aldehyde contribute to the viability of this condensation as well as further transformations.
