Tropylium salts as efficient organic Lewis acid catalysts for acetalization and transacetalization reactions in batch and flow
作者:D. J. M. Lyons、R. D. Crocker、D. Enders、T. V. Nguyen
DOI:10.1039/c7gc01519d
日期:——
carbonyl compounds. Herein we demonstrate for the first time that tropylium salts can act as organic Lewis acid catalysts to facilitate acetalization and transacetalization reactions of a wide range of aldehyde substrates. This metal-free method works efficiently in both batch and flow conditions, prompting further future applications of tropylium organocatalysts in green synthesis.
The azulene ring as a structural element in liquid crystals
作者:Siân E. Estdale、Roger Brettle、David A. Dunmur、Charles M. Marson
DOI:10.1039/a606139g
日期:——
A new approach to the synthesis of azulene liquid crystals is described
based on Hafner’s procedure involving reaction of a pyridinium salt
with a cyclopentadienide. The preparation of a variety of liquid
crystalline materials using this method is described. Variants are
reported with single substituents on the azulene ring in the 6-position
and doubly substituted in the 2, 6- positions. The effect of the azulene
ring as a core or dipolar terminal structural element is explored.
6-(5-Alkyl-1,3-dioxan-2-yl)azulenes are shown to exhibit smectic A phases
and 2-cyclohexyl-6-(5-tridecyl-1,3-dioxan-2-yl)azulene show smectic A and
B phases. Phase characterisation of the materials is recorded together
with X-ray measurements on the smectic A phase of one representative
compound. Results of dichroism studies on the azulene mesogens are also
briefly reviewed.
Provided is a kynurenine production inhibitor comprising a nitrogen-containing heterocyclic compound represented by formula (I):
(wherein R
50
and R
51
may be the same or different and each represent a hydrogen atom or the like, G
1
and G
2
may be the same or different and each represent a nitrogen atom or the like, X represents formula (III):
(wherein m
1
and m
2
may be the same or different and each represent an integer of 0 or 1, Y represents an oxygen atom or the like, and R
6
and R
7
may be the same or different and each represent a hydrogen atom or the like),
R
1
represents optionally substituted lower alkyl or the like, R
2
represents a hydrogen atom or the like, and R
3
represents optionally substituted lower alkyl or the like), and the like.
This invention provides compounds of formula IA-i-a or IB-i-a and subsets thereof:
wherein Z, HY, R
1
, R
2
, R
3
, G
1
, W, n, and A and subsets thereof are as described in the specification. The compounds are inhibitors of PI3K and are thus useful for treating proliferative, inflammatory, or cardiovascular disorders.
Provided is a kynurenine production inhibitor comprising a nitrogen-containing heterocyclic compound represented by formula (I):
(wherein R50 and R51 may be the same or different and each represent a hydrogen atom or the like, G1 and G2 may be the same or different and each represent a nitrogen atom or the like, X represents formula (III):
(wherein m1 and m2 may be the same or different and each represent an integer of 0 or 1, Y represents an oxygen atom or the like, and R6 and R7 may be the same or different and each represent a hydrogen atom or the like),
R1 represents optionally substituted lower alkyl or the like, R2 represents a hydrogen atom or the like, and R3 represents optionally substituted lower alkyl or the like), and the like.