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1.
A series of N‐aryl 2‐alkenamides were produced efficiently by treating N‐aryl 3‐(phenylsulfonyl)‐propanamides with potassium tert‐butoxide in THF at 0°C. With out isolation, it was further treated with an additional equivalent of potassium tert‐butoxide and allyl bromide to give N‐allyl N‐aryl 2‐alkenamides in one pot in good yields. Followed by a ring‐closing metathesis reaction, these N‐allyl N‐aryl 2‐alkenamides were respectively converted into corresponding N‐aryl α,β‐unsaturated γ‐lactams in moderate yields. 相似文献
2.
Kazuaki Ishihara Kazuki Nishimura Katsuya Yamakawa 《Angewandte Chemie (International ed. in English)》2020,59(40):17641-17647
Catalytic enantioselective α‐fluorination reactions of carbonyl compounds are among the most powerful and efficient synthetic methods for constructing optically active α‐fluorinated carbonyl compounds. Nevertheless, α‐fluorination of α‐nonbranched carboxylic acid derivatives is still a big challenge because of relatively high pKa values of their α‐hydrogen atoms and difficulty of subsequent synthetic transformation without epimerization. Herein we show that chiral copper(II) complexes of 3‐(2‐naphthyl)‐l ‐alanine‐derived amides are highly effective catalysts for the enantio‐ and site‐selective α‐fluorination of N‐(α‐arylacetyl) and N‐(α‐alkylacetyl) 3,5‐dimethylpyrazoles. The substrate scope of the transformation is very broad (25 examples including a quaternary α‐fluorinated α‐amino acid derivative). α‐Fluorinated products were converted into the corresponding esters, secondary amides, tertiary amides, ketones, and alcohols with almost no epimerization in high yield. 相似文献
3.
Divvela V. N. Srinivasa Rao Ganala Naga Trinadhachari Koilpillai Joseph Prabahar Ramesh Dandala Meenakshisundaram Sivakumaran Andra Naidu 《Journal of heterocyclic chemistry》2007,44(3):663-667
4.
F. Johari Daha H. Matloubi S. A. Tabatabi B. Shafii A. Shafiee 《Journal of heterocyclic chemistry》2005,42(1):33-37
Condensation of 4‐methylsulfonylaniline with aryl aldehyde in ethanol‐tetrahydrofuran afforded the imino compound 3 . 1,3‐Cycloaddtion of diazomethane with compound 3 followed by oxidazation of the triazoline 4 with potassium permanganate gave 1‐(4‐methylsulfonylphenyl)‐5‐aryl‐1,2,3‐triazoles 5 . Similarly, condensation of 4‐(N,N‐dibenzylaminosulfonyl)aniline with aryl aldehyde followed by 1,3‐cycloaddition of diazomethane with the imino compound 11 and the subsequent oxidation of triazoline 12 with potassium permanganate yielded the triazole 13 . Debenzylation of compound 13 with sulfuric acid gave the desired compound 1‐(4‐aminosulfonylphenyl)5‐aryl‐1,2,3‐triazoles 14 . 相似文献
5.
This article describes the stereo‐ and regioselectivity of the deoxofluorination of N‐terminal dipeptides bearing a serine residue to generate, after rearrangement, α‐fluoro‐β‐amine‐terminated dipeptides. The ratio of the rearranged α‐fluorinated regioisomer is increased, relative to the non‐rearranged β‐fluoro isomer, with N‐alkylated amides. Otherwise, an intramolecular H‐bond between the free amine and the amide NH suppresses formation of the key aziridinium intermediate required for α‐fluorination. N‐Methyl and N‐allyl amides give exclusively α‐fluorination products. Subsequent deprotection of the N‐allyl amide to give a α‐fluoro‐β‐amino dipeptide product is demonstrated. 相似文献
6.
Piotr Kowalski Zbigniew Majka Teresa Kowalska Maria J. Mokrosz Beata Duszynska 《Journal of heterocyclic chemistry》2000,37(1):187-189
The synthesis of new N‐[3‐(4‐aryl‐1‐piperazinyl)propyl] derivatives of 1H‐2,4‐benzoxazin‐3(4H)‐one ( 1a‐b ), 2H‐1,4‐benzoxazin‐3(4H)‐one ( 2a‐b, 3a‐b and 4b ), and benzoxazolin‐2‐one ( 5a‐b ), as biologically active agents, is described. 相似文献
7.
Alexander S. Lyakhov Andrey N. Vorobiov Pavel N. Gaponik Ludmila S. Ivashkevich Vadim E. Matulis Oleg A. Ivashkevich 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o690-o693
In the molecules of 5‐amino‐1‐phenyltetrazole, C7H7N5, (I), and 5‐amino‐1‐(1‐naphthyl)tetrazole, C11H9N5, (II), the tetrazole rings and aryl fragments are not coplanar; corresponding dihedral angles are 50.58 (5) and 45.19 (7)° for the two independent molecules of (I), and 64.14 (5)° for (II). Intermolecular N—H⋯N hydrogen bonds between the amino groups and tetrazole N atoms are primarily responsible for formation of two‐dimensional networks extending parallel to the bc plane in both compounds. The presence of the amino group has a distinct effect on the geometry of the tetrazole rings in each case. 相似文献
8.
A kinetic study of the oxidation of substituted N‐(α‐methylbenzylidene) anilines by dimethyldioxirane was investigated using a UV/VIS spectrophotometer. Oxaziridines and nitrones were formed as intermediates, and in the excess of dimethyldioxirane corresponding carbonyl compounds, nitrosobenzene or nitrobenzene, were formed quantitatively. The kinetic data were used in the equation for the formation of oxaziridines and nitrones as an intermediate and further oxidation to the corresponding acetophenones and nitrosobenzene. Hammett ρ values were determined for compounds p‐substituted on the aromatic ring attached to the carbon atom of the imino group, and it was found that these substituents have very little effect on the oxidation reaction. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 492–497, 2007 相似文献
9.
Enantioselective Formation of 2‐Azetidinones by Ring‐Assisted Cyclization of Interlocked N‐(α‐Methyl)benzyl Fumaramides
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Dr. Alberto Martinez‐Cuezva Dr. Delia Bautista Prof. Dr. Mateo Alajarin Dr. Jose Berna 《Angewandte Chemie (International ed. in English)》2018,57(22):6563-6567
The synthesis of optically active interlocked and non‐interlocked 2‐azetidinones by intramolecular cyclization of N‐(α‐methyl)benzyl fumaramide [2]rotaxanes is described. Two different strategies of asymmetric induction were tested in which the chiral group was located either proximal or distal to the reacting center of the thread. During these experiments, an interesting equilibration process inside the macrocyclic void occurred, thus leading to the cyclization through the (α‐methyl)benzyl carbon atom and giving rise to β‐lactams, with a quaternary carbon atom, in an enantio‐ and diastereocontrolled manner. This cyclization also proceeds in kinetically stable chiral pseudo[2]rotaxanes, thus allowing further dethreading to provide enantioenriched 3,4‐disubstituted trans‐2‐azetidinones. The stereochemical outcomes of the cyclizations inside and outside the macrocycle demonstrated noticeable differences. 相似文献
10.
Novel N‐aryl (and N‐alkyl) γ‐ and δ‐imino esters 2a–g ( 3a–g ) and N‐aryl (and N‐alkyl) ketimines 2h–j ( 3h–j ) were synthesized in high yields (80–99%) from their corresponding γ‐ and δ‐keto esters and ketones in this study. The structures of the synthesized compounds were clarified by Fourier transform infrared (FT‐IR), NMR (1H and 13C), mass spectrometry, and elemental analyses. Isomerizations [E/Z] were also determined by their 1H NMR spectra. The free‐radical scavenging activity of imines was evaluated using the 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) method. The relationships between the structure and antioxidant activity of these compounds are discussed. Among these compounds, 2a–c (at the concentration 1000 μg/mL) exhibit high antioxidant activity similar to those of the standards (butylated hydroxyanisole [ BHA], butylated hydroxytoluene [ BHT], and ascorbic acid). 相似文献
11.
具有β-(1→6)-半乳吡喃糖骨架和α-L-(1→3)-阿拉伯呋喃糖侧链的阿拉伯半乳寡糖的简易合成 总被引:1,自引:0,他引:1
4-Methoxyphenyl glycoside of β-D-Galp-(1→6)-[α-L-Araf-(1→3)-]β-D-Galp-(1→6)-β-D-Galp-(1→6)-{β-D-Galp-(1→6)-[α-L-Araf-(1→3)-]β-D-Galp-(1→6)-β-D-Galp-(1→6)-}2β-D-Galp-(1→6)-[α-L-Araf-(1→)3)-]β-D-Galp-(1→)6)-β-D-Galp was synthesized with 2,3,4,6-tetra-O-benzoyl-α-D-galactopyranosyl trichloroacetimidate (1), 6-O-acetyl-2,3,4-tri-O-benzoyl-α-D-galactopyranosyl trichloroacetimidate (11), 4-methoxyphenyl 3-O-allyl-2,4-tri-O-benzoyl-β-D-galactopyranoside (2),isopropyl 3-O-allyl-2,4-tri-O-benzoyl--thio-β-D-galactopyranoside (12),4-methoxyphenyl 2,3,4-tri-O-benzoyl-β-D-galactopyranoside (5), and 2,3,5-tri-O-benzoyl-α-L-arabinofuranosyl trichloroacetimidate (8) as the key synthons. 相似文献
12.
Rafael Germano Santana Derisvaldo Rosa Paiva Roberto da Silva Gomes Adriana Karla C. A. Reis 《Magnetic resonance in chemistry : MRC》2013,51(5):316-319
The complete assignment of the 1H and 13C NMR spectra of various 2‐acetamido‐3‐mercapto‐3‐methyl‐N‐aryl‐butanamides and 2‐acetamide‐3‐methyl‐3‐nitrososulfanyl‐N‐aryl‐butanamides with p‐methoxy, o‐chloro and m‐chloro substituents is reported. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
13.
One‐Pot Synthesis of 3‐Acetyl‐2‐aryl‐3,4‐dihydroquinazolines from N‐[2‐(Azidomethyl)phenyl]benzamides Utilizing Intramolecular Aza‐Wittig Reaction
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Kazuhiro Kobayashi Naoki Matsumoto Mika Nagashima Hiroki Inouchi 《Helvetica chimica acta》2015,98(2):184-189
A new and convenient method for the preparation of 3,4‐dihydroquinazolines 5 with aryl and Ac groups at C(2) and N(3), respectively, has been developed. The key sequence is the formation of aza‐phosphorane intermediates by the reaction of N‐[2‐(azidomethyl)phenyl]benzamides 1 with Ph3P, followed by intramolecular aza‐Wittig reaction and 3‐acetylation, which can be conducted in one‐pot. 相似文献
14.
Masood Parvez Saqib Ali Sajjad Ahmad Moazzam Hussain Bhatti Muhammad Mazhar 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):m334-m335
The crystal structure of catena‐poly[[tri‐n‐butyltin]‐μ‐3‐(1‐naphthylaminocarbonyl)acrylato‐κ2O1:O3], [Sn(C4H9)3(C14H10NO3)]n, is composed of polymeric chains wherein the metal center exhibits a distorted trigonal‐bipyramidal geometry, with three n‐butyl groups defining the trigonal plane [mean Sn—C 2.133 (7) Å] and the axial positions being occupied by the carboxylate O atoms of two different N‐(1‐naphthyl)maleamate ligands with inequivalent Sn—O distances [2.167 (4) and 2.457 (4) Å]. The N‐(1‐naphthyl)maleamate fragment forms an essentially planar seven‐membered ring involving an intramolecular N—H?O hydrogen bond. 相似文献
15.
Jayaram Reddy Komsani Sreenivas Avula Satish Koppireddi Pranay Kumar Koochana Murty USN Rambabu Yadla 《Journal of heterocyclic chemistry》2015,52(3):764-772
A convenient synthesis of a new series of N‐aryl‐5‐(pyridin‐3‐yl)‐1H/3H‐1,2,3‐triazole‐4‐carbonitriles and alkyl N‐aryl‐5‐(pyridin‐3‐yl)‐1H/3H‐1,2,3‐triazole‐4‐carboxylic acid esters is reported. The newly synthesized 5‐(pyridin‐3‐yl)‐1,2,3‐triazole derivatives are evaluated for their antibacterial and antifungal activity. Some of these triazole derivatives have exhibited moderate antimicrobial activity. 相似文献
16.
Synthesis of 4‐Imino‐2H,3H,5H‐[1,2,5]thiadiazolidin‐1‐oxide through Cycloaddition Reaction of N‐Sulphinylanilines and N‐(α‐Cyano‐α‐aryl)‐methylanilines
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Through the normal mode of cycloaddition reaction of N‐(α‐cyano‐α‐aryl)‐methylanilines ( II ) onto N‐sulphinylanilines ( III ) has provided 2,3,5‐triaryl‐4‐imino‐2H,3H,5H‐[1,2,5]thiadiazolidin‐1‐oxides ( IV ). The present protocol has advantage of convenient operation to synthesize heterocyclics in good yield. 相似文献
17.
A series of new N‐benzoyl‐N‐tert‐butyl‐N′‐(β‐triphenylgermyl)propionylhydrazines were synthesized by the condensation reaction of β‐triphenylgermyl propanoic acid with N‐benzoyl‐N‐tert‐butylhydrazines in good yields by using N,N′‐dicyclohexylcorbodiimide as dehydrating agent. These title compounds were evaluated for molting hormone mimicking activity. The results of bioassay showed that the compounds exhibit moderate larvicidal activity, and toxicity assays indicated that the title compounds can induce a premature, abnormal and lethal larval molt. We found that the title compounds possess potential anticancer activities in vitro. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
18.
Alok K. Mukherjee Subhadra Guha M. Wahab Khan Nitya G. Kundu Madeleine Helliwell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):85-87
Two isoindolin‐1‐one derivatives, (Z)‐3‐benzylidene‐N‐phenylisoindolin‐1‐one, C21H15NO, (II), and (Z)‐3‐benzylidene‐N‐(4‐methoxyphenyl)isoindolin‐1‐one, C22H17NO2, (III), were synthesized by the palladium‐catalysed heteroannulation. The molecules of both compounds have a Z configuration. The interplanar angles between the five‐ and six‐membered rings of the isoindolinone moiety in (II) and (III) are 1.66 (11) and 2.26 (7)°, respectively. The phenyl rings at the N‐position in (II) and (III) are twisted out of the C4N ring plane by 62.77 (11) and 67.10 (7)°, respectively. The substitutions at the N and C‐3 positions of the isoindolinone system have little influence on the molecular dimensions of the resulting compounds. 相似文献
19.
Jun‐Gill Kang Jung‐Pyo Hong Il‐Hwan Suh 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):231-232
In the crystal structure of the title compound, 4‐cyano‐N‐(4‐methoxybenzylidene)phenylamine N‐oxide, C15H12N2O2, the 4‐methoxyphenyl is approximately coplanar with the nitrone moiety but significantly rotated with respect to the 4‐cyanophenyl moiety. The extent of this rotation is significantly different for the two crystallographically independent molecules of the asymmetric unit [dihedral angles of 19.4 (1) and 26.5 (1)°]. The geometry about the C=N bond is Z. The two molecules are related to one another by a pseudo inversion centre. 相似文献
20.
G. Vasuki S. Thamotharan V. Parthasarathi K. Ramamurthi S. Dubey D. P. Jindal 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o598-o599
The title compound, C32H45N2O+·Br?·0.5H2O, has the outer two six‐membered rings in chair conformations, while the central ring is in an 8β,9α‐half‐chair conformation. The five‐membered ring of the steroid nucleus adopts a slightly deformed 14α‐envelope conformation. The pyridylmethylene moiety has an E configuration with respect to the hydroxyl group at position 17. The structure is stabilized by a network of O—H?Br‐type intermolecular hydrogen bonds. 相似文献