- l -Proline as a Valuable Scaffold for the Synthesis of Novel Enantiopure Neonicotinoids Analogs
-
In this research, six neonicotinoid analogs derived from l-proline were synthesized, characterized, and evaluated as insecticides against Xyleborus affinis. Most of the target compounds showed good to excellent insecticidal activity. To the best of our knowledge, this is the first report dealing with the use of enantiopure l-proline to get neonicotinoids. These results highlighted the compound 9 as an excellent candidate used as the lead chiral insecticide for future development. Additionally, molecular docking with the receptor and compound 9 was carried out to gain insight into its high activity when compared to dinotefuran. Finally, the neurotoxic evaluation of compound 9 showed lower toxicity than the classic neonicotinoid dinotefuran.
- Bonilla-Landa, Israel,Cuapio-Mu?oz, Ulises,Luna-Hernández, Axel,Reyes-Luna, Alfonso,Rodríguez-Hernández, Alfredo,Ibarra-Juarez, Arturo,Suarez-Mendez, Gabriel,Barrera-Méndez, Felipe,Caram-Salas, Nadia,Enríquez-Medrano, J. Francisco,Díaz De León, Ramón E.,Olivares-Romero, José Luis
-
p. 1455 - 1465
(2021/02/16)
-
- RAS INHIBITORS AND METHODS OF USING THE SAME
-
Provided herein are compounds identified as inhibitors of KRAS protein activity that can be used to treat various diseases and disorders, such as cancer.
- -
-
-
- CHEMOKINE RECEPTOR MODULATORS AND USES THEREOF
-
Disclosed herein, inter alia, are compounds and methods of use thereof for the modulation of chemokine receptor activity.
- -
-
-
- Exploring steric effects in diastereoselective synthesis of chiral aminophenolate zinc complexes and stereoselective ring-opening polymerization of rac-lactide
-
A series of tridentate chiral aminophenol proligands and corresponding zinc complexes, LZnX (L = (S)-2-{[(1-R4-2-pyrrolidinyl)CH2N(R3)-]CH2}-6-R1-4-R2-C6H2O, X = N(SiMe3)2, R3 = nBu, R4 = Bn: R1 = R2 = Cl (1), R1 = R2 = Me (2), R1 = R2 = tBu (3); X = N(SiMe3)2, R1 = trityl, R2 = Me: R3 = n-octyl, R4 = Bn (4), R3 = Bn, R4 = Bn (5), R3 = nBu, R4 = naphthalen-1-ylmethyl (6), R3 = nBu, R4 = iPr (7); R1 = R2 = cumyl, R3 = Et, R4 = Bn: X = N(SiMe3)2 (8), X = OtBu (9), X = Et (10), X = Cl (11)), have been synthesized. Complexes 4, 6, and 11 were obtained as enantiopure products (4 and 6 as enantiopure a; 11 as enantiopure b), while complexes 1-3, 5, and 7-10 as a pair of diastereomers, but in different ratios, which have been proved by X-ray diffraction and NMR spectroscopic studies. When exposed to the ring-opening polymerization of rac-lactide, most of these complexes can effectively produce PLAs with narrow polydispersities, desirable molecular weights, and moderate to high isotacticities. The structure-selectivity relationships, including the relationships of structure-synthesis diastereoselectivity and structure-polymerization stereoselectivity, have been further investigated. Consistent trends of diastereoselectivity and stereoselectivity are observed with the variations of the R1 group at the ortho-position of the phenolate ring and the R3 group in the pyrrolidinyl moiety. The decrease of the steric bulkiness of the R4 group on the central amine has less influence on the diastereoselectivity, but leads to considerable loss of the stereoselectivity, whereas the decrease of the steric bulkiness of the X group results in a reverse of the diastereoselectivity, but shows no influence on the stereoselectivity. There is probably no direct relationship between the diastereoselectivity in complex synthesis and the stereoselectivity of the complex toward the ROP of rac-LA. The stereocontrol of these complexes might largely rely on the substituents in the ligand framework rather than their diastereomer ratios.
- Wang, Haobing,Yang, Yang,Ma, Haiyan
-
p. 7356 - 7372
(2016/08/06)
-
- Optically active imidazole N-oxides derived from l-prolinamine1
-
Starting with (S)-1-benzylprolinamine and α-hydroxyimino ketones, enantiomerically pure bisheterocyclic imidazole N-oxides bearing the (S)-configured N-benzyl(pyrrolidin-2-yl)methyl residue were prepared. These N-oxides reacted with 2,2,4,4-tetramethylcyclobutane-1,3-dithione to give the corresponding optically active imidazole-2-thione derivatives via a sulfur transfer reaction. Reduction of the N-oxides with Raney-nickel led to deoxygenation, whereas catalytic hydrogenation (Pd/C) in ethanol occurred with simultaneous deoxygenation and debenzylation, leading to optically active 1-(pyrrolidin-2-yl)methyl-1H-imidazoles. Alkylation of the prepared imidazole N-oxides and their respective imidazoles with butyl and hexyl bromide and subsequent anion exchange gave optically active N-alkoxy- and N-alkylimidazolium tetrafluoroborates, respectively, with the properties of 'room temperature ionic liquids'.
- Mloston, Grzegorz,Wroblewska, Aneta,Obijalska, Emilia,Heimgartner, Heinz
-
p. 958 - 965
(2013/09/23)
-
- Synthesis and structure-activity relationships of naphthamides as dopamine D3 receptor ligands
-
A series of naphthamides were synthesized, and the affinities of these compounds were determined for dopamine D2 and D3 receptors using radioligand binding techniques. The naphthamide compounds that were prepared include N-(1- alkylp
- Huang,Luedtke,Freeman,Wu,Mach
-
p. 1815 - 1826
(2007/10/03)
-
- Catalytic epoxidation of unfunctionalized alkenes by dinuclear nickel(II) complexes
-
The synthesis, crystal and molecular structure and catalytic activity in epoxidation reactions of new dinuclear nickel(II)-complexes, octahedral μ-diacetato-μ-[2,6-bis[N-2-2'-pyridylethyl)formimidoyl]phenolato]bis nickel(II)·perchlorate·methanol (6) and square planar (μ-hydroxo-μ-[2,6-bis[N-((S)-1-benzyl-2-yl-pyrrolidine)formimidoyl]p henolato]bisnickel(II)·bisperchlorate (7), are described. For the preparation of 7 a new 5-step route for homochiral bisamine (S)-benzyl-2-aminomethyl-pyrrolidine (19) was developed starting from (S)-proline. Epoxidation of unfunctionalized alkenes with sodium hypochlorite and tert-butyl hydroperoxide as terminal oxidants was effectively catalyzed with bisnickel(II)-complexes 6 and 7, and a turnover of 165 was reached using trans-β-methylstyrene (34). The epoxidations probably proceed via a radical intermediate (such as OCl·) and no enantioselectivity is obtained under phase transfer conditions. In epoxidation reactions employing tert-butyl hydroperoxide as terminal oxidant a turnover of 43 was obtained with trans-stilbene (30) as substrate. Unexpectedly in the case of styrene (29) 1,2-bis-(tert-butylperoxy)ethylbenzene (59) was isolated as the major product.
- Rispens, Minze T.,Gelling, Onko Jan,De Vries, Andre H.M.,Meetsma, Auke,Van Bolhuis, Fre,Feringa, Ben L.
-
p. 3521 - 3546
(2007/10/03)
-
- TRANSITION METAL COMPLEXES - A NEW CLASS OF CATALYSTS OF INTERFACIAL ALKYLATION FOR THE ASYMMETRICAL SYNTHESIS OF α-AMINO ACIDS
-
A new class of catalysts of interfacial asymmetrical alkylation is suggested for the synthesis of α-amino acids - positively charged complexes of the transition metals Cu(II), Ni(II), and Pd(II).These complexes consist of several fragments, by variation of which the structure of the catalysts can readily be modified.The complexes are chiral on account of (S)proline derivatives contained in them as one of the fragments.The catalyst complexes (C) were used in alkylation of amino acid fragments of Ni(II) complexes of the Schiff base of glycine with N-(2-pyridinecarbonyl)-o-aminobenzophenone (Ni-PBP-Gly) and the Schiff base of alanine with N-(2-pyridinecarbonyl)-o-aminobenzaldehyde (Ni-PBA-Ala) under interfacial conditions.After decomposition of alkylated complexes, phenylalanine and α-methyl-phenylalanine were isolated with yields of 33-87percent and optical purity (o. p.) from 3 to 21percent, depending on the C used.
- Belokon', Yu. N.,Maleev, V. I.,Videnskaya, S. O.,Saporovskaya, M. B.,Tsyryapkin, V. A.,Belikov, V. M.
-
p. 110 - 118
(2007/10/02)
-