- Ru-NHC-Catalyzed Asymmetric Hydrogenation of 2-Quinolones to Chiral 3,4-Dihydro-2-Quinolones
-
Direct enantioselective hydrogenation of unsaturated compounds to generate chiral three-dimensional motifs is one of the most straightforward and important approaches in synthetic chemistry. We realized the Ru(II)-NHC-catalyzed asymmetric hydrogenation of 2-quinolones under mild reaction conditions. Alkyl-, aryl- and halogen-substituted optically active dihydro-2-quinolones were obtained in high yields with moderate to excellent enantioselectivities. The reaction provides an efficient and atom-economic pathway to construct simple chiral 3,4-dihydro-2-quinolones. The desired products could be further reduced to tetrahydroquinolines and octahydroquinolones.
- Daniliuc, Constantin,Glorius, Frank,Hu, Tianjiao,Lückemeier, Lukas
-
p. 23193 - 23196
(2021/09/25)
-
- Lactamization of alkenyl C-H bonds to generate 2-quinolinones with triphosgene
-
A simple and easy-going method is developed to synthesize the analogues of 2-quinolinones by using triphosgene (BTC) as the carbonyl source. In these reactions, both the toxic carbon monoxide (CO) and phosgene are avoided and the 2-quinolinones are obtained in moderate to good yields under mild conditions, all of which are anticipated to be meaningful in both industry and laboratory.
- Du, Guizhi,Wang, Zixiao,Zhang, Zhen
-
p. 600 - 608
(2020/06/03)
-
- HFIP-mediated strategy towards β-oxo amides and subsequent Friedel-Craft type cyclization to 2?quinolinones using recyclable catalyst
-
A simple and cost-effective 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)-mediated protocol for the synthesis of β-oxo amides has been described by using amines and β-keto esters as substrates. The reaction conditions were found to be highly efficient towards the cleavage of C[sbnd]O bond and consequent formation of the products in excellent yields and selectivity. The obtained β-oxo amides were further transformed in to the synthetically useful 2?quinolinones via intramolecular Friedel-Craft type cyclization of aromatic ring using ferrites as a recyclable catalyst. A spectrum of substrates bearing broad range of functional groups were well tolerated under the reaction conditions. The proposed mechanistic pathways were substantially verified by literature and mass-spectroscopic evidences.
- Kabi, Arup K.,Gujjarappa, Raghuram,Vodnala, Nagaraju,Kaldhi, Dhananjaya,Tyagi, Ujjawal,Mukherjee, Kalisadhan,Malakar, Chandi C.
-
-
- Synthesis and antileishmanial evaluation of thiazole orange analogs
-
Cyanine compounds have previously shown excellent in vitro and promising in vivo antileishmanial efficacy, but the potential toxicity of these agents is a concern. A series of 22 analogs of thiazole orange ((Z)-1-methyl-4-((3-methylbenzo[d]thiazol-2(3H)-ylidene)methyl)quinolin-1-ium salt), a commercial cyanine dye with antileishmanial activity, were synthesized in an effort to increase the selectivity of such compounds while maintaining efficacy. Cyanines possessing substitutions on the quinolinium ring system displayed potency against Leishmania donovani axenic amastigotes that differed little from the parent compound (IC50 12–42 nM), while ring disjunction analogs were both less potent and less toxic. Changes in DNA melting temperature were modest when synthetic oligonucleotides were incubated with selected analogs (ΔTm ≤ 5 °C), with ring disjunction analogs showing the least effect on this parameter. Despite the high antileishmanial potency of the target compounds, their toxicity and relatively flat SAR suggests that further information regarding the target(s) of these molecules is needed to aid their development as antileishmanials.
- Abdelhameed, Ahmed,Liao, Xiaoping,McElroy, Craig A.,Joice, April C.,Rakotondraibe, Liva,Li, Junan,Slebodnick, Carla,Guo, Pu,Wilson, W. David,Werbovetz, Karl A.
-
supporting information
(2019/11/28)
-
- Discovery, synthesis and molecular substantiation of N-(benzo[d]thiazol-2-yl)-2-hydroxyquinoline-4-carboxamides as anticancer agents
-
The effort was taken to develop a series of benzothiazole and quinoline fused bioactive compounds obtained through a four-step synthetic route using a range of substituted acetoacetanilides. Achieved N-(benzo[d]thiazol-2-yl)-2-hydroxyquinoline-4-carboxamides (6a-l) were produced up to 96% of yield while the eco-friendly p-TSA used as a catalyst. Further, the anticancer activity of these compounds was determined using a range of cancer cell lines starting from MCF-7 (Breast cancer), HCT-116 (Colon cancer), PC-3 & LNCaP (Prostate) and SK-HEP-1 (Liver cancer). Present study compounds were also testified for antioxidant properties prior to anticancer studies since the Reactive Oxygen Species (ROS) being vital in cancer development. To determine the cell membrane stability effects of the compounds, human red blood cells (HRBC) based membrane protection assay was determined. In the results, compounds 6a-l were able to produce a dominated result values over PC3 cell lines (Prostate cancer) than the other cell lines used in this study. Since the connectivity of human germ cell alkaline phosphatase (hGC-ALP) in the development of prostate cancer is known, the most active compounds were evaluated for the hGC-ALP inhibition in order to ensure a mechanism of anticancer action of these compounds. The mode of interaction and binding affinity of these compounds was also investigated by a molecular docking study. In the results, 6d, 6i, 6k, and 6l were found with least IC50 values 0.075 μM and highest relative activity of 92%, 90%, and 96% respectively. The need for further animal model evaluation and pre-clinical studies recognized.
- Bindu,Vijayalakshmi,Manikandan
-
-
- Synthesis of 2-Quinolinones via a Hypervalent Iodine(III)-Mediated Intramolecular Decarboxylative Heck-Type Reaction at Room Temperature
-
A hypervalent iodine(III)-mediated intramolecular decarboxylative Heck-type reaction of 2-vinyl-phenyl oxamic acids has been developed. The unique ring-strain-enabled radical decarboxylation mechanism is preliminarily revealed. This protocol features metal-free reaction conditions and operational simplicity, allowing the lactamization of 2-vinylanilines using a readily accessible carbonyl source and the synthesis of various 2-quinolinones with excellent chemoselectivity at room temperature.
- Fan, Huaqiang,Pan, Peng,Zhang, Yongqiang,Wang, Wei
-
p. 7929 - 7932
(2019/01/04)
-
- Compounds having anticonvulsion activity, preparing methods thereof and applications of the compounds
-
The invention provides 7-substituted-5-methyl-1,2,4-triazolo[4,3-a] quinoline and 7-substituted-5-ethoxy-[1,2,4]-triazolo[4,3-a] quinoline compounds having anticonvulsion activity, preparing methods thereof and applications of the compounds in the field of preparing anticonvulsion medicines.
- -
-
Paragraph 0051; 0052; 0053; 0054
(2017/10/05)
-
- Lactamization of sp2C?H Bonds with CO2: Transition-Metal-Free and Redox-Neutral
-
The first direct use of carbon dioxide in the lactamization of alkenyl and heteroaryl C?H bonds to synthesize important 2-quinolinones and polyheterocycles in moderate to excellent yields is reported. Carbon dioxide, a nontoxic, inexpensive, and readily available greenhouse gas, acts as an ideal carbonyl source. Importantly, this transition-metal-free and redox-neutral process is eco-friendly and desirable for the pharmaceutical industry. Moreover, these reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization.
- Zhang, Zhen,Liao, Li-Li,Yan, Si-Shun,Wang, Lei,He, Yun-Qi,Ye, Jian-Heng,Li, Jing,Zhi, Yong-Gang,Yu, Da-Gang
-
supporting information
p. 7068 - 7072
(2016/07/06)
-
- Design and synthesis of novel coumarin analogs and their nematicidal activity against five phytonematodes
-
The presence of hydroxyl groups at the C4 and C7 positions in coumarin backbone has been proposed as a potential modification site for providing excellent bioactivity according to previous studies. A series of novel coumarin derivatives were rationally designed and synthesized by use of a complex catalytic system for a targeted modification at the above sites. These derivatives were assayed for nematicidal activity. As predicted, the derivatization enhanced the activity of the coumarins against five nematodes. Compounds 7b, 9a, 10c and 11c showed significant strong nematicidal broad spectrum activity against all tested nematodes. Compound 10c was the most effective with the lowest LC50 values against Meloidogyne incognita (5.1 μmol/L), Ditylenchus destructor (3.7 μmol/L), Bursaphelenchus mucronatus (6.4 μmol/L), Bursaphelenchus B. xylophilus (2.5 μmol/L) and Aphelenchoides besseyi (3.1 μmol/L), respectively. A brief investigation on the structure-activity relationships (SAR) revealed that the targeted modification by a C7 hydroxyl was optimum compared with that of a C4 hydroxyl and that the coupling chain length was crucial for the nematicidal activity.
- Pan, Le,Li, Xiu-Zhuang,Sun, Di-An,Jin, Hui,Guo, Hong-Ru,Qin, Bo
-
supporting information
p. 375 - 379
(2016/03/19)
-
- Ruthenium-catalyzed cyclization of anilides with substituted propiolates or acrylates: An efficient route to 2-quinolinones
-
A Ru-catalyzed cyclization of anilides with propiolates or acrylates affording 2-quinolinones having diverse functional groups in good to excellent yields is described. Later, 2-quinolinones were converted into 3-halo-2-quinolinones and 2-chloroquinolines
- Manikandan, Rajendran,Jeganmohan, Masilamani
-
supporting information
p. 3568 - 3571
(2014/07/21)
-
- An environmentally benign one pot synthesis of substituted quinolines catalysed by fluoroboric acid based ionic liquid
-
Organic synthesis generally required large amount of solvent, avoiding the use of organic solvents in synthesis is a paradigm shift directed at developing more benign chemistry, and with ionic liquids surprisingly can lead to access to new compounds. An elegant one-pot synthesis of quinoline derivatives has been achieved by reaction of substituted anilines with β-ketoester at 60°C in ethanol using an ionic liquid [Et3NH]+[BF 4]- as catalyst. All the reactions gave products with high degree of purity and excellent yield (78.93%) within the shorter span of time (20.65 min) than those reactions with conventional methods. The screening of solvents as well as the reuse of ionic liquid has been evaluated. The structure of the products has been elucidated by spectral and analytical data. The present scope and potential economic impact of the reaction are demonstrated by the synthesis of substituted quinolines. Remaining challenges and future perspectives of the new transformation are discussed.
- Rajendran, A.,Karthikeyan, C.,Rajathi, K.,Ragupathy, D.
-
p. 877 - 881,5
(2020/09/09)
-
- Characterization of 4-methyl-2-oxo-1,2-dihydroquinolin-6-yl acetate as an effective antiplatelet agent
-
We have studied earlier a membrane bound novel enzyme Acetoxy Drug: protein transacetylase identified as Calreticulin Transacetylase (CRTAase) that catalyzes the transfer of acetyl groups from polyphenolic acetates (PAs) to the receptor proteins and thus modulating their biological activities. In this communication, we have reported for the first time that acetoxy quinolones are endowed with antiplatelet action by virtue of causing CRTAase catalyzed activation of platelet Nitric Oxide Synthase (NOS) by way of acetylation leading to the inhibition of ADP/Arachidonic acid (AA)-dependent platelet aggregation. The correlation of specificity of platelet CRTAase to various analogues of acetoxy quinolones with intracellular NO and consequent effect on inhibition of platelet aggregation was considered crucial. Among acetoxy quinolones screened, 6-AQ (4-methyl-2-oxo-1,2-dihydroquinolin-6-yl acetate/6-acetoxyquinolin-2-one, 22) was found to be the superior substrate to platelet CRTAase and emerged as the most active entity to produce antiplatelet action both in vitro and in vivo. 6-AQ caused the inhibition of cyclooxygenase-1 (Cox-1) resulting in the down regulation of thromboxane A2 (TxA2) and the inhibition of platelet aggregation. Structural modification of acetoxy quinolones positively correlated with enhancement of intracellular NO and antiplatelet action.
- Priya, Nivedita,Gupta, Anjali,Chand, Karam,Singh, Prabhjot,Kathuria, Abha,Raj, Hanumantharao G.,Parmar, Virinder S.,Sharma, Sunil K.
-
experimental part
p. 4085 - 4094
(2010/08/06)
-
- An environmentally benign indium (III) chloride catalysed one-pot synthesis of quinolines
-
A convenient eco-friendly procedure for the quantitative synthesis of novel quinoline derivatives has been developed by a simple one-pot reaction of substituted anilines with P-ketoesters at 60°C in ethanol using recyclable indium chloride as catalyst. The reaction proceeds smoothly under solvent free conditions with quantitative yields.
- Kidwai, Mazaahir,Bansal, Vikas,Mishra, Neeraj Kumar,Bhatnagar, Divya
-
experimental part
p. 746 - 748
(2009/12/28)
-
- NOVEL NITROGENATED HETEROCYCLIC COMPOUND AND SALT THEREOF
-
A nitrogen-containing heterocyclic compound represented by the general formula: wherein the dashed line represents a single bond or a double bond; R1, R2, R3, R4 and R5 independently represent a hydrogen atom, halogen atom, a lower alkyl, aryl, lower alkoxy or monocyclic heterocyclic group which may be substituted or the like; R6 represents a lower alkyl, aryl, monocyclic heterocyclic, bicyclic heterocyclic or tricyclic heterocyclic group which may be substituted; X1 represents a lower alkylene group or the like; X2 represents a lower alkylene, lower alkenylene or lower alkynylene group which may be substituted; X3 represents an oxygen atom, sulfur atom, a sulfinyl group, sulfonyl group or the like; Y1 represents a bivalent cyclic group, containing a nitrogen, which may be substituted or the like; and Z1 represents a nitrogen atom, a carbon atom which may be substituted or the like, or a salt thereof. The compound or salt has a potent antibacterial activity and a high safety, and is therefore useful as an excellent antibacterial agent.
- -
-
-
- Microwave-assisted solvent-free synthesis of 4-methyl-2-hydroxy- And 2-methyl-4-hydroxyquinolines
-
Rapid and efficient microwave-assisted synthesis of 4-methyl-2-hydroxy- and 2-methyl-4-hydroxyquinolines from anilines and ethyl acetoacetate under different conditions is described.
- Nadaraj,Selvi, S. Thamarai
-
p. 1203 - 1207
(2008/09/18)
-
- Process for the preparation of anti-malarial drugs
-
The invention relates to novel intermediates and processes for the preparation of quinoline compounds useful as anti-malarial drugs and novel intermediates useful in the process. A process for the preparation of a compound of formula (I) in which R1is C1-6alkyl; R2and R3are independently hydrogen, halogen, trifluoromethyl or C1-6alkoxy; R4is C1-6alkyl; R5is hydrogen or C1-6alkyl; and R6or amino which comprises reacting a compound of formula (II) in which R1, R4and R5are as defined in formula (I) and X is a leading group with a compound of formula (III).
- -
-
-
- Quinoline-4-acetamides as sPLA2 inhibitors
-
Quinoline-4-acetamides were designed as potential phospholipase A2 inhibitors by structural based method and synthesized. The chemical structures of the obtained compounds were confirmed by elemental analyses, 1H NMR and MS. Preliminary bioassay study shows that quinoline-4-acetamides display certain inhibition to sPLA2.
- Liu, Ying,Feng, Yabing,Wang, Renxiao,Gao, Ying,Lai, Luhua
-
p. 1639 - 1641
(2007/10/03)
-
- Substituent effects on absorption and fluorescence spectra of carbostyrils
-
Absorption and fluorescence spectra as well as quantum yields of a series of differently substituted carbostyrils (quinolin-2(1H)-ones) are reported. Especially for compounds containing donor substituents in position 6, substantial bathochromic shifts (comparable to analogous coumarins) of both absorption as well as fluorescence transitions are obtained. High absorption intensities and quantum yields are found for 7-donor substituted isomers. Semiempirical molecular orbital calculations (AMI for structures, ZINDO for electronic transition energies) prove to be a suitable tool for the prediction of absorption and fluorescence properties of these compounds. Ab initio and density functional calculations establish the lactam form as the dominant tautomer of the parent quinolin-2(1H)-one.
- Fabian, Walter M.F.,Niederreiter, Karlheinz S.,Uray, Georg,Stadlbauer, Wolfgang
-
p. 209 - 220
(2007/10/03)
-
- Pyridine and related aza heterocycle derivatives as cardiovascular agents
-
Novel pharmaceutical compounds and compositions having nitrogen containing ring systems which may be represented by the following structural formula: wherein R1 or R3 is a moiety of the formula: wherein R6 is selected from either hydrogen or acetyl; R7 is selected from 2, 3 or 4-pyridyl or 1-imidazolyl and Q is -(CH2)n, where n is an integer from 1 to 5 and R1 and R2, R2 and R3, R3 and R4 or R4 and R5 taken together may be -CH=CH-CH=CH-. The compounds and compositions are useful as inhibitors of thromboxane synthetase and in the treatment of hypertension and arrythmia in mammals.
- -
-
-
