共查询到20条相似文献,搜索用时 15 毫秒
1.
Dr. Kunihiro Matsumura Dr. Keisuke Nishikawa Hiroaki Yoshida Toshiki Niwa Yuichiro Fushii Dr. Matsumi Doe Prof. Dr. Yoshiki Morimoto 《化学:亚洲杂志》2021,16(14):1882-1886
Histrionicotoxin (HTX) alkaloids isolated from the poison arrow frogs possess a unique structure characterized by a 1-azaspiro[5.5]undecane skeleton common to the HTX family. The unique molecular architecture of HTXs and the interest as potential target drugs have prompted synthetic chemists to promote the total synthesis so far. However, all of the synthetic strategies to access the 1-azaspiro[5.5]undecane framework of HTXs take a multistep approach from linear starting materials due to stepwise construction of either six-membered carbo- or azacycle. Herein, we report the direct one-step construction of the 1-azaspiro[5.5]undecane skeleton from linear amino ynone substrates bearing an N-methoxycarbonyl group utilizing our mercuric triflate (Hg(OTf)2)-catalyzed cycloisomerization reaction. The utility of this novel methodology was demonstrated by the total and formal syntheses of HTX-235A and HTX-283A, respectively, from the azaspirocycle. 相似文献
2.
Brian E. Kornberg Sham S. Nikam Michael F. Rafferty 《Journal of heterocyclic chemistry》1999,36(5):1271-1277
This paper describes the synthesis of several new 2,3-dimethoxy-6-methyl-7-nitro-quinoxaline-5-carboxylic acid derivatives ( 13a-m ) via a multistep synthetic route from 5-methyl-1H-benzo[d][1,3]oxazine-2,4-dione ( 1 ). 相似文献
3.
Dejiang Li Deqing Long Heqing Fu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):519-526
1,3-bis[(3-aryl)-s-triazolo[3,4-b]-[1,3,4]thiadiazole-6-yl]benzenes 2 were synthesized in high yields by the reaction of 3-aryl 4-amino-5-mercapto-1,2,4-triazole 1 with m-phthalic acid. 相似文献
4.
This review presents a survey of synthetic methods and reaction mechanism of the dibenzo[d,f][1,3] dioxepine derivatives. Furthermore, the influence of the substituent groups in 6,6′‐position of dibenzo[d,f][1,3] dioxepine on their conformation is explored. The functional dibenzo[d,f][1,3] dioxepine synthetically versatiles substrate, as they can be used for synthesis of a large variety of π‐conjugated oligomer and polymer containing heterocyclic compounds, such as dibromination dibenzo[d,f][1,3] dioxepine derivative as a raw material of synthesis for organic semiconductor polymers. The synthetic and fluorescent property of π‐conjugated polymers basic on dibenzo[d,f][1,3] dioxepine also is explored. J. Heterocyclic Chem., (2012). 相似文献
5.
Jie Su Mykola Telychko Shaotang Song Jiong Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7730-7740
Triangulene and its higher homologues are a class of zigzag-edged triangular graphene molecules (ZTGMs) with high-spin ground states. These open-shell molecules are predicted to host ferromagnetically coupled edge states with net spin values scaling with molecular size and are therefore considered promising candidates for future molecular spintronics applications. Unfortunately, the synthesis of unsubstituted [n]triangulenes and the direct observation of their edge states have been a long-standing challenge due to a high reactivity towards oxygen. However, recent advances in precursor design enabled the on-surface synthesis and characterization of unsubstituted [3]-, [4]-, and [5]triangulene. In this Minireview, we will highlight key aspects of this rapidly developing field, ranging from the principles of precursor design to synthetic strategies and characterization of a homologous series of triangulene molecules synthesized on-surface. We will also discuss challenges and future directions. 相似文献
6.
Mohammad Hossein Mosslemin Mohammad Reza Nateghi Razieh Mohebat 《Monatshefte für Chemie / Chemical Monthly》2008,13(3):1247-1250
A clean, simple, one-pot, and efficient synthesis of 1,2-dihydro-1-aryl[1,3]oxazino[5,6-f]quinolin-3-one and 1,2-dihydro-1-arylnaphtho[1,2-e]-[1,3]oxazine-3-one derivatives was accomplished in good yields via reaction between 6-quinolinol or 2-naphthol, aromatic aldehydes, and methyl carbamate in aqueous medium catalyzed by TEBA (triethylbenzylammonium chloride). 相似文献
7.
Jie Su Mykola Telychko Shaotang Song Jiong Lu 《Angewandte Chemie (International ed. in English)》2020,59(20):7658-7668
Triangulene and its higher homologues are a class of zigzag‐edged triangular graphene molecules (ZTGMs) with high‐spin ground states. These open‐shell molecules are predicted to host ferromagnetically coupled edge states with net spin values scaling with molecular size and are therefore considered promising candidates for future molecular spintronics applications. Unfortunately, the synthesis of unsubstituted [n]triangulenes and the direct observation of their edge states have been a long‐standing challenge due to a high reactivity towards oxygen. However, recent advances in precursor design enabled the on‐surface synthesis and characterization of unsubstituted [3]‐, [4]‐, and [5]triangulene. In this Minireview, we will highlight key aspects of this rapidly developing field, ranging from the principles of precursor design to synthetic strategies and characterization of a homologous series of triangulene molecules synthesized on‐surface. We will also discuss challenges and future directions. 相似文献
8.
Kai Zhang Mélissa El Bitar Nehme Philip A. Hope Michel Rickhaus 《Helvetica chimica acta》2023,106(4):e202200195
Embedding seven-membered rings into polycyclic aromatic molecules is attractive as they can exert an influence on molecular conformation that ultimately changes the solubility and π-electronics. The considerations in designing and synthesizing a highly strained azatriseptane framework are discussed herein. We employ a twofold macrocyclization strategy to form the [7,7,7]-system and through scoping various strategies identify that the Friedel–Crafts approach is the key. In addition to the successes presented here, the synthetic limitations we have identified highlight the key challenges in forming triseptane frameworks and pave the way for second-generation analogues that may have various applications in optical and electronic organic materials. 相似文献
9.
Dr. Yu-Ping He Rui Quan Xing-Zi Li Prof. Dr. Jieping Zhu Prof. Dr. Hua Wu 《Angewandte Chemie (International ed. in English)》2023,62(18):e202217954
An unprecedent asymmetric catalytic benzilic amide rearrangement for the synthesis of α,α-disubstituted piperazinones is reported. The reaction proceeds via a domino [4+1] imidazolidination/formal 1,2-nitrogen shift/1,2-aryl or alkyl migration sequence, employing readily available vicinal tricarbonyl compounds and 1,2-diamines as starting materials. This approach provides an efficient access to chiral C3-disubsituted piperazin-2-ones with high enantiocontrol, which are exceedingly difficult to access from the existing synthetic methodologies. The observed enantioselectivity was proposed to be controlled by dynamic kinetic resolution in the 1,2-aryl/alkyl migration step. The resulting densely functionalized products are versatile building blocks to bioactive natural products, drug molecules and their analogues. 相似文献
10.
From‐Core and From‐End Direct CH Arylations: A Step‐Saving New Synthetic Route to Thieno[3,4‐c]pyrrole‐4,6‐dione (TPD)‐Incorporated D‐‐π–A–π–D Functional Oligoaryls 下载免费PDF全文
Po‐Han Lin Kuan‐Ting Liu Prof. Dr. Ching‐Yuan Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8754-8757
In contrast to the traditional multistep synthesis, herein an efficient and fewer‐steps new synthetic strategy is demonstrated for the facile preparation of organic‐electronically important D–π–A–π–D‐type oligoaryls through sequential direct C?H arylations. This methodology has shown that the synthesis of thieno[3,4‐c]pyrrole‐4,6‐dione (TPD)‐ or furano[3,4‐c]pyrrole‐4,6‐dione (FPD)‐centred target molecules could be accessed step‐economically either from the core structure (acceptor) or from the end structure (donor), which supplied a more flexible and succinct new synthetic alternative to the preparation of the π‐functional small‐molecule semiconducting materials. In addition, optical and electrochemical properties of the synthesized oligoaryls were examined. 相似文献
11.
Mohammad Hossein Mosslemin Mohammad Reza Nateghi Razieh Mohebat 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1247-1250
A clean, simple, one-pot, and efficient synthesis of 1,2-dihydro-1-aryl[1,3]oxazino[5,6-f]quinolin-3-one and 1,2-dihydro-1-arylnaphtho[1,2-e]-[1,3]oxazine-3-one derivatives was accomplished in good yields via reaction between 6-quinolinol or 2-naphthol, aromatic aldehydes, and methyl carbamate in aqueous medium catalyzed by TEBA (triethylbenzylammonium chloride).
Correspondence: Mohammad Hossein Mosslemin, Department of Chemistry, Islamic Azad University, Yazd 8916871967, Iran. 相似文献
12.
By condensation of 6-aminoquinoline with methyl 2-(benzo[d][1,3]dioxol-5-yl)-4,6-dioxocyclohexanecarboxylate and aldehydes of aromatic, heteroaromatic, and cyclohexene series new 4,7-phenanthroline
derivatives were synthesized. The reaction performed in 1-butanol proceeded regiospecifically and with a moderate degree of
stereoselectivity resulting in a mixture of cis- and trans-methyl 9-(benzo-[d][1,3] dioxol-5-yl)-12-aryl(heteryl, cyclohexenyl)-11-oxo-7,8,9,10,11,12-hexahydrobenzo-[b][4,7]-phenanthroline-10-carboxylates (∼30: 70). 相似文献
13.
José Barluenga Prof. Dr. Jaime García‐Rodríguez Silvia Martínez Dr. Ángel L. Suárez‐Sobrino Dr. Miguel Tomás Prof. Dr. 《化学:亚洲杂志》2008,3(4):767-775
The reactivity of Fischer alkenyl carbenes toward 8‐azaheptafulvenes is examined. Alkenyl carbenes react with 8‐azaheptafulvenes with complete regio‐ and stereoselectivity through formal [8+3] and [8+2] heterocyclization reactions, which show an unprecedented dependence on the Cβ substituent at the alkenyl carbene complex. Thus, the formal [8+3] heterocyclization reaction is completely favored in carbene complexes that bear a coordinating moiety to give tetrahydrocyclohepta[b]pyridin‐2‐ones. Otherwise, alkenyl carbenes that lack appropriate coordinating groups undergo a formal [8+2] cyclization with 8‐azaheptafulvenes to give compounds that bear a tetrahydroazaazulene structure. A likely mechanism for these reactions would follow well‐established models and would involve a 1,4‐addition/cyclization in the case of the [8+2] cyclization or a 1,2‐addition/[1,2] shift–metal‐promoted cyclization for the [8+3] reaction. The presence of a coordinating moiety in the carbene would favor the [1,2] metal shift through transition‐state stabilization to lead to the [8+3] product. All these processes provide an entry into the tetrahydroazaazulene and cycloheptapyridone frameworks present in the structure of biologically active molecules. 相似文献
14.
Tukaram S. Choudhare Devendra S. Wagare Vijay T. Kadam Prashant D. Netankar 《Journal of heterocyclic chemistry》2021,58(8):1637-1644
The present investigation describe the synthesis of 8-(benzyloxy)-5-(2-[1,3-diphenyl-1H-pyrazol-4-yl]thiazol-4-yl)quinolin-2(1H)-one derivatives. Quinolin-8-ol was transformed by five step synthetic procedures into 8-Benzyloxy-5-(2-bromo-acetyl)-1H-quinolin-2-one. Subsequently, 8-Benzyloxy-5-(2-bromo-acetyl)-1H-quinolin-2-one condensed with 1,3-Diphenyl-1H-pyrazole-4-carbothioic acid amide in the presence of acetonitrile to afford 8-(benzyloxy)-5-(2-[1,3-diphenyl-1H-pyrazol-4-yl]thiazol-4-yl)quinolin-2(1H)-one derivatives. Synthesized compounds were screened for their antimicrobial activity against gram-positive and gram-negative bacteria. Most of the synthesized compounds are found to be active against tested bacterial strains and fungal strain. 相似文献
15.
Eva Schendera Lisa-Natascha Unkel Phung Phan Huyen Quyen Gwen Salkewitz Frank Hoffmann Alexander Villinger Prof. Dr. Malte Brasholz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(1):269-274
A metal-free, photoinduced aerobic tandem amine dehydrogenation/Povarov cyclization/aromatization reaction between N-aryl glycine esters and indoles leads to tetracyclic 11H-indolo[3,2-c]quinolines under mild conditions and with high yields. The reaction can be performed by using molecular iodine along with visible light, or by combining an organic photoredox catalyst with a halide anion. Mechanistic studies reveal that product formation occurs through a combination of radical-mediated oxidation steps with an iminium ion or N-haloiminium ion [4+2]-cycloaddition, and the N-heterocyclic products constitute new analogues of the antiplasmodial natural alkaloid isocryptolepine. 相似文献
16.
D. H. Russell M. L. Gross J. Van Der Greef N. M. M. Nibbering 《Journal of mass spectrometry : JMS》1979,14(9):474-481
New experimental data on the rearrangement reaction of various phenoxyethyl halides to give [C6H6O]+˙ are presented and compared with previous studies so that a coherent picture of this process can be developed. By examining the metastable kinetic energy release for low energy decomposing molecular ions of the phenoxyethyl halides, it has been concluded that formation of [C6H6O] occurs by competitive 1,2 and 1,3 hydrogen shifts from the alkyl carbons to oxygen followed by a rate determining C? O bond cleavage. This is substantiated by the absence of a primary hydrogen isotope effect. For more highly activated molecular ions, a new mechanism comes into play as evidenced by the appearance of a small hydrogen isotope effect. It is postulated that this third mechanism involves transfer of the alkyl hydrogen to the ortho position of the ring by a rate determining 1,5 shift, followed by a 1,3 hydrogen shift from the ortho methylene group to oxygen and rapid C? O bond cleavage. This 1,3 hydrogen shift to oxygen appears to be ‘catalysed’ by the halogen atoms yielding phenol ions. No indications have been found for the formation of tautomeric 2,4-cyclohexadienone ions. Furthermore, highly activated molecular ions produce [C6H6O]+˙ which can undergo metastable decomposition to lose carbon monoxide. Kinetic energy release measurements for the latter reaction show that the majority of these [C6H6O]+˙ions have been formed as phenol ions as well. These arguments are supported by energetic measurements and by comparisons with previous ion cyclotron resonance and collisional activation studies. 相似文献
17.
Previously unknown 7-aryl(hetaryl)-3-methyl-7,10,11,12-tetrahydro-9H-benzo[b][1,7]phenanthrolin-8-ones and their 10,10-dimethyl-substituted analogs were synthesized by three-component condensation of
2-methylquinolin-5-amine with aromatic aldehydes and cyclic β-diketones (cyclohexane-1,3-dione and dimedone) in butyl alcohol. 相似文献
18.
Dr. Robert Thoran Tristan Schuh Philipp Holling Dr. Florian Puls Dr. Olga Kataeva Prof. Dr. Hans-Joachim Knölker 《European journal of organic chemistry》2023,26(35):e202300591
The iron-catalyzed oxidative C−C homocoupling of diarylamines affords 2,2′-bis(arylamino)-1,1′-biaryls which represent crucial synthetic building blocks for an access to a range of seven-membered heterocyclic ring systems. Reaction with paraformaldehyde, diphenyl carbonate, and diphenyl sulfite as efficient 1,1-dielectrophiles led to dibenzo[d,f][1,3]diazepines, dibenzo[d,f][1,3]diazepinones, and dibenzo[c,e][1,2,7]thiadiazepine 6-oxides. The synthetic procedures enable short and practical routes to these 1,3-diazepine derivatives under mild reaction conditions and with a high tolerance of various functional groups. 相似文献
19.
Radim Horák Kamil Kořistek Veronika Šamšulová Ludmila Slaninová Martin Grepl Lubomír Kvapil Petr Funk Pavel Hradil Miroslav Soural 《Journal of heterocyclic chemistry》2020,57(4):1605-1615
Compounds bearing [1,3]dioxolo-quinoline scaffolds have been found in quinoline-based natural products; the only exception is the [1,3]dioxolo[4,5-c]quinoline moiety with a rare occurrence in both natural and synthetic derivatives. In this article, we report the preparation of diversely substituted and functionalized [1,3]dioxolo[4,5-c]quinolines using [1,3]dioxolo[4,5-c]quinoline-4-carbaldehyde (DQC) as the common intermediate. DQC was synthesized on a large scale from anthranilic acid and chloroacetone as the starting materials, with the rearrangement of acetonyl-anthranilate as the key step. The developed method allows for the simple preparation of [1,3]dioxolo[4,5-c]quinolines with various C2 substituents on the quinoline scaffold. Additionally, the synthetic route was successfully applied to the preparation of 3-hydroxyquinoline-4(1H)-ones. The target compounds were tested against representative Gram-positive/negative bacteria, and two derivatives exhibited submicromolar minimum inhibitory concentrations against Micrococcus luteus. 相似文献
20.
A novel method for synthesis of 2-R-5-Ar(Het)-5,6-dihydro-7H-[1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones by condensation of 3-R-4,5-dihydro-1H-1,2,4-triazole-5-thiones with 3-aryl(heteryl)-2-propenoyl chlorides is proposed. 相似文献