Novel π<sub>2s</sub>+π<sub>2a</sub>Electrocyclization of Triethylenic-Malonic Acids Exemplified for a One-Pot Synthesis of New γ-Dilactones<i>cis</i>-Fused with a Cyclopentene
作者:Jean-Marc Dillenschneider、Laurent Dufossé、Mireille Fouillaud、Nuthathai Sutthiwong、Roger Labia、Alain Valla
DOI:10.1002/jhet.2419
日期:2016.7
cyclopentenic ring via cyclization of 7‐chlorotriethylenic‐malonic acids. The key step implicates an intramolecular cyclization to a cyclopentenyl cation, according to an electrocyclic π2s + π2a conrotatory process. This cyclopentenyl cation led to unstable γ‐lactones intermediates that are rearrange to more stable isomers. δ‐lactones (6Z and 6E‐(3‐chlorobut‐2‐en‐2‐yl)‐5‐methyl‐3,6‐dihydro‐2H‐pyran‐2‐one)
Two-step Synthesis of New γ-Lactones via Cyclization of 7-Chloro-2-(methoxycarbonyl)-4-6-dimethylocta-(2<i>E</i>,4<i>E</i>,6<i>E</i>)-trienoic acid
作者:Jean-Marc Dillenschneider、Laurent Dufossé、Mireille Fouillaud、Nuthathai Sutthiwong、Roger Labia、Alain Valla
DOI:10.1002/jhet.2444
日期:2016.9
A new rapid synthesis of γ‐lactones, cis fused with a cyclopentenic ring by thermal cyclization of 7‐chloro‐2‐(methoxycarbonyl)‐4‐6‐dimethylocta‐7‐phenyl (or methyl) (2E,4E,6E)‐trienoic acids was reported. The key step implicates an intramolecular cyclization to a cyclopentenyl cation, according to an electrocyclic π2s + π2a conrotatory process, published in a recent paper (from the corresponding diacids)
Oxidation of 3,6-dihydro-2H-selenopyrans with an electron-withdrawing group at the 2 position proceeded via an unprecedented ring-contraction to afford selenophenes.
Hetero cyclic metallocene compounds and use thereof in catalyst system for producing olefin polymers
申请人:——
公开号:US20030036612A1
公开(公告)日:2003-02-20
1
A metallocene compound of general formula (I): LGZMXp, wherein L is a divalent group, Z is a moiety of formula (II), wherein R
3
and R
4
are selected from hydrogen and hydrocarbon groups; A and B are selected from S, O or CR
5
, wherein R
5
is selected from hydrogen and hydrocarbon groups, either A or B being different from CR
5
; G is a moiety of formula (III), wherein R
6
, R
7
, R
8
and R
9
are selected from hydrogen and hydrocarbon groups, M is an atom of a transition metal, X is selected from a halogen atom, a R
10
, OR
10
, OSO
2
CF
3
, OCOR
10
, SR
10
, NR
10
2
or PR
10
2
group, wherein the substituents R
10
is hydrogen and a hydrocarbon group; p is an integer from 0 to 3.
The present invention provides novel inhibitors of the enzyme D-amino acid oxidase. The compounds of the invention are useful for treating or preventing diseases and/or condition, wherein modulation of D-serine levels, and/or its oxidative products, is effective in ameliorating symptoms. The invention further provides methods of enhancing learning, memory and/or cognition. For example, the invention provides methods for treating or preventing loss of memory and/or cognition associated with neurodegenerative diseases, such as Alzheimer's disease. The invention further provides methods for preventing loss of neuronal function characteristic of neurodegenerative diseases. In addition, methods are provided for the treatment or prevention of neuropsychiatric diseases (e.g., schizophrenia) and for the treatment or prevention of pain and ataxia.