l-Proline derived nitrogenous steroidal systems: an asymmetric approach to 14-azasteroids
作者:Ritesh Singh、Gautam Panda
DOI:10.1039/c3ra42272k
日期:——
intramolecular SN2′ cyclization reaction for the construction of critical C-ring in the nitrogen impregnated steroidal architectures bearing unsaturation at Δ9(11) position. In the endeavour to synthesize some new congeners, the remote electronic impact of the electron donating groups in A ring and heteroatoms like oxygen in Bring, on the propensity of C-ring cyclization was also observed.
已经描述了在温和的反应条件下使用L-脯氨酸来访问14-氮杂类固醇的有效手性池方法。关键步骤涉及分子内的S N 2'环化反应,以在含氮的甾族结构中在Δ9 (11)位置携带不饱和键,以构建关键的C环。为了合成一些新的同类物,还观察到了A环上给电子基团和B环上的氧等杂原子对C环环化倾向的远程电子影响。
Enantioselective Copper-Catalyzed Arylation-Driven Semipinacol Rearrangement of Tertiary Allylic Alcohols with Diaryliodonium Salts
作者:Daniel H. Lukamto、Matthew J. Gaunt
DOI:10.1021/jacs.7b05340
日期:2017.7.12
A copper-catalyzed enantioselective arylative semipinacol rearrangement of allylic alcohols using diaryliodonium salts is reported. Chiral Cu(II)-bisoxazoline catalysts initiate an electrophilic alkene arylation, triggering a 1,2-alkyl migration to afford a range of nonracemic spirocyclic ketones with high yields, diastereo- and enantioselectivities.
the heavier halogens (bromine and iodine) second, the scope and limitations of the halogenative phase‐transfer methodology will be discussed and compared. An extension of the fluorination/semi‐pinacol reaction to the ring‐expansion of five‐membered allylic cyclopentanols will be also described, as well as some preliminary results on substrates prone to desymmetrization will be given. Finally, the present
sulfonylation/semipinacol rearrangements of allylic alcohols were developed using cheap and stable RSO2Na (R = CF3, Ph) as reagents. Various β-trifluoromethyl and sulfonated ketones were obtained in moderate to excellent yields. This strategy provides a facile, direct, and complementary approach to construct all-carbon quaternary stereocenters. In addition, the reaction has the advantages of being chemical oxidant-free
[EN] FUNGICIDAL 5-SUBSTITUTED IMIDAZOL-1-YL CARBINOL DERIVATIVES<br/>[FR] DÉRIVÉS D'IMIDAZOL-1-YL CARBINOL SUBSTITUÉS EN POSITION 5 SERVANT DE FONGICIDES
申请人:BAYER AG
公开号:WO2020070050A1
公开(公告)日:2020-04-09
The present invention relates to novel compounds of formula (I), wherein R1, R2 and R3 are defined as in the claims and specification, and R4 represents a bicyclic moiety of formula (Q), wherein the dotted line A represents a single or double bond, and X1, X2, X3, X4 and X5 are defined as in the claims and specification. It further relates to processes for preparing said compounds, to compositions comprising these compounds, and to the use thereof as biologically active compounds, especially for control of harmful microorganisms in crop protection and in the protection of materials and as plant growth regulators.