The mechanism of the spontaneous autoxidation of dihydroartemisinic acid
摘要:
Dihydroartemisinic acid undergoes slow spontaneous autoxidation to artemisinin and other natural products, which have been reported from the medicinal plant Artemisia annua. The mechanism of this complex transformation is shown to involve four steps: (i) initial reaction of the Delta(4.5)-double bond of dihydroartemisinic acid with molecular oxygen, (ii) Hock cleavage of the resulting tertiary allylic hydroperoxide; (iii) oxygenation of the enol product from Hock cleavage; and (iv) cyclization of the resulting vicinal hydroperoxyl-aldehyde to the 1,2,4-trioxane system of artemisinin. (C) 2002 Elsevier Science Ltd. All rights reserved.
Practical conversion of artemisinic acid in desoxyartemisinin
作者:Mankil Jung、Hala N. ElSohly、Edward M. Croom、Andrew T. McPhail、Donald R. McPhail
DOI:10.1021/jo00376a070
日期:1986.12
RAVINDRANATHAN, KUMAR M. ANIL;MENON, RANI B.;HIREMATH, S. V., TERNAHEDRON LETT., 31,(1990) N, C. 755-758
作者:RAVINDRANATHAN, KUMAR M. ANIL、MENON, RANI B.、HIREMATH, S. V.
DOI:——
日期:——
The mechanism of the spontaneous autoxidation of dihydroartemisinic acid
作者:Lai-King Sy、Geoffrey D Brown
DOI:10.1016/s0040-4020(01)01193-0
日期:2002.1
Dihydroartemisinic acid undergoes slow spontaneous autoxidation to artemisinin and other natural products, which have been reported from the medicinal plant Artemisia annua. The mechanism of this complex transformation is shown to involve four steps: (i) initial reaction of the Delta(4.5)-double bond of dihydroartemisinic acid with molecular oxygen, (ii) Hock cleavage of the resulting tertiary allylic hydroperoxide; (iii) oxygenation of the enol product from Hock cleavage; and (iv) cyclization of the resulting vicinal hydroperoxyl-aldehyde to the 1,2,4-trioxane system of artemisinin. (C) 2002 Elsevier Science Ltd. All rights reserved.
Synthesis of [15,15,15-<sup>2</sup>H<sub>3</sub>]-Dihydroartemisinic Acid and Isotope Studies Support a Mixed Mechanism in the Endoperoxide Formation to Artemisinin
作者:Kaitlyn Varela、Hadi D. Arman、Francis K. Yoshimoto
DOI:10.1021/acs.jnatprod.1c00246
日期:2021.7.23
trideuterated dihydroartemisinicacid isotopologues at C3 and C15 converted to artemisinin at a slower rate compared to nondeuterated dihydroartemisinicacid, revealing a kinetic isotope effect in the initial ene reaction toward endoperoxide formation (kH/kD ∼ 2–3). (iii) The rate of conversion from dihydroartemisinicacid to artemisinin increased with the amount of dihydroartemisinicacid, suggesting
青蒿素是用于治疗疟疾的植物天然产物。青蒿素的内过氧化物桥赋予其抗寄生虫特性。双氢青蒿酸是青蒿素的生物合成前体,先前已证明其以非酶促方式经历内过氧化物形成以产生青蒿素。本报告公开了[15,15,15- 2 H 3]-二氢青蒿酸及其用于确定内过氧化物形成机制的用途。进行了一些新的观察:(i) 紫外线-C (UV-C) 辐射最初加速了青蒿素的形成,随后促进了 O-O 键的均裂和青蒿素重排为不同的产物,以及 (ii) 双氘和三氘双氢青蒿素与未氘化的双氢青蒿酸相比,C3 和 C15 处的酸性同位素转化为青蒿素的速度较慢,揭示了在初始 ene 反应中对内过氧化物形成 (k H /k D)的动力学同位素效应∼ 2–3)。(iii) 从双氢青蒿酸到青蒿素的转化率随着双氢青蒿酸的量增加而增加,表明分子间相互作用促进了内过氧化物的形成,并且 (iv) 18 O 2标记显示三个和四个氧原子从分子氧中掺入到青蒿素