Intramolecular nucleophilic acyl substitution reactions of halo-substituted esters and lactones. New applications of organosamarium reagents
摘要:
Intramolecular nucleophilic acyl substitution reactions involving a broad range of halo substituted carboxylic acid derivatives have been accomplished in excellent yield employing samarium(II) iodide as the reductive coupling agent. Although particular substrates cyclized most effectively in THF in the presence of tripiperidinophosphine oxide, carboxylic acid esters, the focus of this report, cyclize equally well without such an additive in the presence of a catalytic quantity of iron(III) complexes. Thus a comprehensive series of halo substituted esters were cyclized in excellent yield to the corresponding 4-, 5-, and 6-membered carbocycles. The reaction is extremely mild and selective as demonstrated by experiments wherein alkyl chlorides, acetals, and olefins remain completely intact under the reaction conditions. In addition to introducing a convenient procedure for preparing stereodefined spirocyclic systems, a new ring expansion sequence has been developed that appears extremely general for the preparation of various ring systems.
The invention relates to compounds of formula
where hetaryl I, hetaryl II,
R
1
,
R
2
,
R
3
, R
4
, m, n, and o are as defined in the specification
or to pharmaceutically active acid addition salts thereof. The compounds of formula I are modulators for amyloid beta and thus may be useful for the treatment or prevention of a disease associated with the deposition of β-amyloid in the brain, in particular Alzheimer's disease, and other diseases such as cerebral amyloid angiopathy, hereditary cerebral hemorrhage with amyloidosis, Dutch-type (HCHWA-D), multi-infarct dementia, dementia pugilistica and Down syndrome.
该发明涉及以下式的化合物
其中hetaryl I,hetaryl II,
R
1
,
R
2
,
R
3
,R
4
,m,n和o如规范中所定义
或其药用活性酸盐。式I的化合物是淀粉样蛋白β的调节剂,因此可能对与大脑中β-淀粉样蛋白沉积相关的疾病的治疗或预防有用,特别是阿尔茨海默病,以及其他疾病,如脑淀粉样血管病,遗传性脑出血伴淀粉样变性,荷兰型(HCHWA-D),多梗塞性痴呆,拳击性痴呆和唐氏综合征。
Photoinduced Copper‐Catalyzed Asymmetric Decarboxylative Alkynylation with Terminal Alkynes
作者:Hai‐Dong Xia、Zhong‐Liang Li、Qiang‐Shuai Gu、Xiao‐Yang Dong、Jia‐Heng Fang、Xuan‐Yi Du、Li‐Lei Wang、Xin‐Yuan Liu
DOI:10.1002/anie.202006317
日期:2020.9.21
photoinduced copper‐catalyzed asymmetric radical decarboxylative alkynylation of bench‐stable N‐hydroxyphthalimide(NHP)‐type esters of racemic alkyl carboxylic acids with terminal alkynes, which provides a flexible platform for the construction of chiral C(sp3)−C(sp) bonds. Critical to the success of this process are not only the use of the copper catalyst as a dual photo‐ and cross‐coupling catalyst but
developed. Enantioselective construction of quaternary carbon centers by utilizing Pd-catalyzed asymmetric allylic alkylation proved its feasibility. An efficient and practical method for the synthesis of α,α-disubstituted six-membered lactones was developed. Enantioselective construction of quaternary carbon centers by utilizing Pd-catalyzed asymmetric allylic alkylation proved its feasibility.
IMIDAZO-OXADIAZOLE AND IMIDAZO-THIADIAZOLE DERIVATIVES
申请人:Ares Trading S.A.
公开号:US20150175628A1
公开(公告)日:2015-06-25
The present invention provides compounds of Formula (I) used as Amyloid beta lowering agent for the treatment of neurodegenerative diseases.
本发明提供了一种公式(I)的化合物,用作淀粉样β降低剂,用于治疗神经退行性疾病。
Bicyclic Compounds for the Reduction of Beta-Amyloid Production
申请人:Marcin Lawrence R.
公开号:US20110015175A1
公开(公告)日:2011-01-20
The present disclosure provides a series of compounds of the formula (I)
which reduce β-amyloid peptide (β-AP) production and are useful in the treatment of Alzheimer's Disease and other conditions affected by β-amyloid peptide (β-AP) production.