79631-04-2Relevant articles and documents
Fenton chemistry enables the catalytic oxidative rearrangement of indoles using hydrogen peroxide
Zhao, Guodong,Liang, Lixin,Wang, Eryu,Lou, Shaoyan,Qi, Rui,Tong, Rongbiao
supporting information, p. 2300 - 2307 (2021/04/12)
Oxidative rearrangement of indoles is an important transformation to yield 2-oxindoles and spirooxindoles, which are present in many pharmaceutical agents and bioactive natural products. Previous oxidation methods show either broad applicability or greenness but rarely achieve both. Reported is the discovery of Fenton chemistry-enabled green catalytic oxidative rearrangement of indoles, which has wide substrate scope (42 examples) and greenness (water as the only stoichiometric byproduct) at the same time. Detailed mechanistic studies revealed that the Fenton chemistry generated hydroxyl radicals that further oxidize bromide to reactive brominating species (RBS: bromine or hypobromous acid). Thisin situgenerated RBS is the real catalyst for the oxidative rearrangement. Importantly, the RBS is generated under neutral conditions, which addresses a long-lasting problem of many haloperoxidase mimics that require a strong acid for the oxidation of bromide with hydrogen peroxide. It is expected that this new catalytic Fenton-halide system will find wide applications in organic synthesis.
Synthesis and fungicidal activity of tryptophan analogues–the unexpected calycanthaceous alkaloid derivatives
Zheng, Shaojun,Gu, Yongdong,Li, Longbo,Zhu, Rui,Cai, Xingwei,Bai, Hongjin,Zhang, Jiwen
, p. 1142 - 1149 (2017/02/26)
A series of 21?N-protected tryptophan derivatives were synthesised from tryptophan in good yields. Their structures were characterised by IR,1H NMR,13C NMR, DEPT (90° and 135°) and MS analysis. The synthesised compounds were evaluated against a wide variety of plant pathogen fungi. Compounds a19 and a21 displayed activity against Fusarium oxysporum (F. oxysporum), and compound a21 showed high activity against F. oxysporum and Eggplant Verticillium, with EC50values of 58.27 and 77.39?μg?mL?1, respectively. Considering that the bioassay of the title compounds was evaluated, effects of the chain alkyl substituents may contribute to the significant variations in fungicidal potency. Their structure–antifungal activity relationships were also discussed. These results will pave the way for further design, structural modification and development of calycanthaceous alkaloids as antimicrobial agents.
Synthesis of tryptophans by Lewis acid promoted ring-opening of aziridine-2-carboxylates: Optimization of protecting group and Lewis acid
Tirotta, Ilaria,Fifer, Nathan L.,Eakins, Julia,Hutton, Craig A.
, p. 618 - 620 (2013/02/23)
The preparation of tryptophan derivatives through the Lewis acid promoted substitution of aziridine carboxylates with indole was found to be accompanied by a ring-expansion reaction to generate an oxazolidinone byproduct. The ratio of tryptophan to oxazol
