Rhodium(II)-catalyzed intramolecularreaction of diazoketones 1 bearing a cyclic ethereal moiety transiently formed bicyclo[m.3.0]octan-3-one-1-oxonium-2-ylides (2), which underwent sigmatropic and stereospecific [3 + 2] cycloreversion reaction to form alkenyloxyketenes 3. The ketenes were efficiently trapped by methanol to form the corresponding esters 4. Mechanistic studies revealed that the size
铑(II)催化的带有环醚部分的重氮酮1的分子内反应瞬时形成双环[ m .3.0] octan-3-one-1-oxonium-2-ylides(2),其经历了σ和立体定向性[3 + 2 ]环还原反应,形成烯基氧乙烯酮3。乙烯酮被甲醇有效地捕集,形成相应的酯4。机理研究表明,醚环的大小至少可在THF至THP,氧杂环丁烷和氧杂环丁烷部分范围内变化,即m= 3-6。另一方面,含有羰基单元的ylide环的尺寸被限制为五元环。如通过在键裂解位置带有甲基的非对映异构体对的反应所证明的,发现环还原是立体特异性的。从苏式异构体7中,仅形成(E)-烯基氧乙酸酯15(77-84%),而从赤型异构体8中,形成(Z)-异构体16形成了(80-88%)。在使用杂化密度泛函B3LYP和高度相关的二次构型相互作用QCISD方法进行计算的基础上,分析了重氮丙酮取代的环醚经双环氧鎓烷基化物裂解为链烯基氧乙烯酮的机理,揭示了协同的[3
3-Carbamoyl-2-Pyridone Derivative
申请人:Ishizuka Natsuki
公开号:US20080103139A1
公开(公告)日:2008-05-01
The present invention provides compounds having an agonistic activity to the cannabinoid receptor, which is represented by the formula (I):
wherein R
1
is optionally substituted C1-C8 alkyl and the like; R
2
is C1-C6 alkyl; R
3
is C1-C6 alkyl and the like; or R
2
and R
3
taken together with may form an optionally substituted 5 to 10 membered non-aromatic carbon ring; R
4
is hydrogen and the like; G is a group selected from the groups shown by the formula an the like:
wherein R
5
is hydrogen and the like; X
1
is a single bond and the like; X
2
is optionally substituted C1-C8 alkylene that may be replaced by one or two groups of —O—, or —N(R
6
)—, wherein R
6
is hydrogen and the like, and the like; X
3
is a single bond and the like;
a pharmaceutically acceptable salt or a solvate thereof, and pharmaceutical compositions, atopic dermatitis treating agents, and anti-pruritus agents, especially anti-pruritus agents for oral used and for external application, which each contains the said compound as an active ingredient.