Rhodium(<scp>iii</scp>)-catalyzed regioselective distal <i>ortho</i> C–H alkenylation of <i>N</i>-benzyl/furanylmethylpyrazoles directed by <i>N</i>-coordinating heterocycles
作者:Hyewon Kim、Raju S. Thombal、Hari Datta Khanal、Yong Rok Lee
DOI:10.1039/c9cc06758b
日期:——
C–H activation of challenging N-benzylpyrazoles was accomplished by employing rhodium(III) catalysis. This C–H activation reaction proceeds via a six-membered rhodacycle intermediate and enables distal regioselective alkenyl-functionalization on the aromaticring of N-benzylpyrazoles without the formation of bis-adducts. High functional group tolerance, low catalyst loading, and superior reactivity
具有挑战性的N-苄基吡唑类化合物的C–H活化是通过铑(III)催化完成的。这种C–H活化反应是通过六元的Rhodacycle中间体进行的,可在N-苄基吡唑的芳香环上进行远端区域选择性烯基官能化,而不会形成双加合物。该方案的一些吸引人的特征是高官能团耐受性,低催化剂负载量和烯烃部分对N-苄基吡唑的优异反应性。该方案为吲唑,苯并[ d ] [1,2,3]三唑和1-(呋喃-3-基甲基)-1 H的区域选择性官能化提供了广阔的范围。-吡唑产率高。
5-HYDROXYPYRIMIDINE-4-CARBOXAMIDE COMPOUND
申请人:Kuribayashi Takeshi
公开号:US20110112103A1
公开(公告)日:2011-05-12
The present invention provides compounds which promote erythropoietin production. Compounds represented by the following general formula (1) or pharmacologically acceptable salts thereof are provided:
[wherein, R
1
represents a group —X-Q
1
, X-Q
1
-Y-Q
2
or X-Q
1
-Y-Q
2
-Z-Q
3
, X represents a single bond, —CH
2
— or the like, Q
1
represents a monocyclic or bicyclic heterocyclic group which may have substituent(s), Y represents a single bond, —CH
2
—, or the like, Q
2
represents a monocyclic or bicyclic hydrocarbon ring group which may have substituent(s) or a monocyclic or bicyclic heterocyclic group which may have substituent(s), Z represents a single bond, —CR
11
R
12
— or the like, R
11
and R
12
each independently represents a hydrogen atom, a halogen atom or the like, Q
3
represents a phenyl group which may have substituent(s), a C
3
-C
7
cycloalkyl group which may have substituent(s), a C
3
-C
7
cycloalkenyl group which may have substituent(s) or a monocyclic or bicyclic heterocyclic group which may have substituent(s), R
2
represents a C
1
-C
3
alkyl group or the like, and R
3
represents a hydrogen atom or a methyl group].
A series of brominated 1‐benzylpyrazoles were deprotonated at the pyrazole 5‐position or the benzylic position on treatment with lithium diisopropylamide in tetrahydrofuran at low temperature. The obtained organolithium intermediates were subjected to reaction with Me3SiCl, t‐BuNCO, ClCONEt2 or ClCON(i‐Pr)2 affording the respective silanes or amides after hydrolysis.
Palladium-Catalyzed [5 + 2] Rollover Annulation of 1-Benzylpyrazoles with Alkynes: A Direct Entry to Tricyclic 2-Benzazepines
作者:Alejandro Suárez-Lustres、Nuria Martínez-Yáñez、Álvaro Velasco-Rubio、Jesús A. Varela、Carlos Saá
DOI:10.1021/acs.orglett.2c04300
日期:2023.2.10
first Pd-catalyzed [5 + 2] rollover annulation of 1-benzylpyrazoles with alkynes to assemble 10H-benzo[e]pyrazolo[1,5-a]azepines (tricyclic 2-benzazepines) has been developed. The rollover annulation implies a twofold C–H activation of aryl and heteroaryl Csp2–H bonds (C–H/C–H) of 1-benzylpyrazoles (five-atom partners) and alkynes to give the [5 + 2] annulated compounds.
Structural alterations to the benzylic position of the first drug-like selective angiotensin II AT(2) receptor agonist (1) have been performed, with the emphasis to reduce the CYP 450 inhibitory property of the initial structure. The imidazole moiety, responsible for the CYP 450 inhibitory effect in 1, was replaced with various heterocycles. In addition, the modes of attachment of the heterocycles, that is, carbon versus nitrogen attachment, and introduction of carbonyl functionalities to the benzylic position have been evaluated. In all the three series, AT(2) receptor ligands with affinity in the lower nanomolar range were identified. None of the analogues, regardless of the substituents, exhibited any affinity for the AT(1) receptor. Compounds with substantially reduced inhibition of the CYP 450 enzymes were obtained. Among them the compound 60 was found to induce neurite elongation in NG 108-15 cells and served as potent AT(2) selective agonist. (C) 2010 Elsevier Ltd. All rights reserved.