Eco-compatible sonochemical synthesis of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones using green TiO2.
ABSTRACT: A green and an aqueous-mediated sonochemical synthesis of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones from the multi-component reaction of Meldrum's acid, 3,4-methylenedioxy aniline and various aromatic aldehydes is described in the presence of catalytic amount of TiO2 NPs for the first time using high power sonicator. Initially, TiO2 NPs has also been synthesized by the biochemical method using leaf extract of Origanum majorana plant as a reducing and capping agent under sonication. Under the sonication, the catalytic activity of synthesized TiO2 NPs found to be excellent for synthesis of a series of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones with operational simplicity, high yield under green reaction conditions without any environmental issue. The structure of TiO2 NPs was characterized by FT-IR, SEM, TEM, XRD and EDX studies.
Project description:Dihydroberberine (systematic name: 9,10-dimethoxy-6,8-dihydro-5H-1,3-dioxolo[4,5-g]isoquinolino[3,2-a]isoquinoline), C20H19NO4, a reduced form of pharmacologically important berberine, crystallizes from ethanol without interstitial solvent. The molecule shows a dihedral angle of 27.94?(5)° between the two arene rings at the ends of the molecule, owing to the partial saturation of the inner quinolizine ring system. Although lacking classical O-H or N-H donors, the packing in the crystalline state is clearly governed by C-H···N and C-H···O hydrogen bonds involving the two acetal-type C-H bonds of the 1,3-dioxole ring. Each dihydroberberine molecule is engaged in four hydrogen bonds with neighbouring molecules, twice as donor and twice as acceptor, thus forming a two-dimensional sheet network that lies parallel to the (100) plane.
Project description:Four series of novel 4-morpholino-7,8-dihydro-5H-thiopyrano[4,3-d]pyrimidine derivatives 11a-j, 12a-j, 13a-g and 14a-g bearing phenylpyridine/phenylpyrimidine- carboxamide scaffolds were designed, synthesized and their IC50 values against three cancer cell lines (A549, PC-3 and MCF-7) were evaluated. Eleven of the compounds showed moderate cytotoxicity activity against the cancer cell lines. Structure-activity relationships (SARs) and pharmacological results indicated that the introduction of phenylpyridine-carboxamide scaffold was beneficial for the activity. What's more, the oxidation of the sulfur atom in thiopyran and various types of substituents on the aryl group have different impacts on different series of compounds. Furthermore, the positions of aryl group substituents have a slight impact on the activity of the phenylpyridine-carboxamide series compounds.
Project description:Quinolin-2(1H)-ones and phenanthridin-6(5H)-ones are synthesized in high yields by K2CO3-promoted cyclization of N-aryl-?-bromo-?,?-unsaturated amides and N-aryl-2-bromobenzamides in dimethylformamide under microwave irradiation.
Project description:The first examples of thiazolo[4,5-e]benzoisoxazoles are obtained from bromination of dihydrobenzo[d]isoxazol-4(5H)-one followed by cyclocondensation with thiourea, in the presence of DDQ. Analogously, cyclocondensation with thioamides provided 7,8-dihydrothiazolo[4,5-e]benzoisoxazoles. A 55-member library of these heterocycles is reported.
Project description:Efficient optimization procedures in chiral catalysis are usually linked to a straightforward strategy to access groups of structurally similar catalysts required for fine-tuning. The ease of building up such ligand libraries can be increased when the structure-modifying step (introduction of a substituent) is done at a later stage of the synthesis. This is demonstrated for the extended family of di- and tetranaphtho azepinium compounds, widely used as chiral phase transfer catalysts (PTC). Using 2,6-diiodo-4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepine and 4,8-diiodo-6,7-dihydro-5H-dibenzo[c,e]azepine, respectively, as key intermediates, 18 spiro-azepinium compounds were synthesized in a total yield of 25-42% over 6-7 steps from 1,1'-binaphthyl-2,2'-dicarboxylic acid or diphenic acid, respectively. The replacement of iodo groups with aryl substituents was performed as the last or the penultimate step of the synthesis.
Project description:<h4>Background</h4>The formation of novel N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-benzopyrano [3,4-c]pyridines were observed unexpectedly during the acid-mediated ketal removal of ethylenedioxy ketal protected 4-piperidones. The literature revealed that benzopyranopyridine derivatives are of scientific interest and some exhibit interesting biological activities. Diastereomeric resolution was utilized to isolate optically pure chiral molecules.<h4>Results</h4>The acid catalyzed deprotection of N-substituted-4,4-ethylenedioxy-3- [(1,3-benzodioxol-5-yloxy)methyl]piperidines, prepared by condensation of the corresponding phenols and mesylate derivatives, unexpectedly resulted in cyclodehydration leading to new benzopyrano derivatives, N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-benzopyrano [3,4-c]pyridines. The process involves the deprotection of the carbonyl protecting group, and then the cyclization reaction occurs followed by dehydration to give the final product.These N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-benzopyrano [3,4-c] pyridines were dealkylated giving the corresponding N-unsubstituted derivatives. The cis-1,3,4,4a,5,10b-hexahydro-[6,7]-2H-benzopyrano [3,4-c]pyridine derivative was also obtained from the N-benzylated-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-benzopyrano [3,4-c]pyridine via catalytic hydrogenation. The resolution of the enantiomers was carried out using D-(-)-mandelic acid as chiral reagent. The absolute configuration of the S,S-mandelate salt derivative was determined by X-ray crystallographic analysis.<h4>Conclusion</h4>The approach led to the construction of N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-benzopyrano [3,4-c] pyridines ring systems involving the one-pot deprotection, cyclization and dehydration of N-substituted-4,4-ethylenedioxy-3- [(1,3-benzodioxol-5-yloxy)methyl]piperidines. The hydrogenation of the N-benzylated benzopyrano [3,4-c]pyridine derivative followed by resolution led to the formation of a new compound.
Project description:The synthesis of 5-substituted 6,6a-dihydroisoindolo[2,1-a]quinolin-11(5H)-ones via [4 + 2] imino-Diels-Alder cyclization from N-aryl-3-hydroxyisoindolinones and N-vinyl lactams under Lewis acid-catalysed anhydrous conditions is reported. Reactions of N-(2-substituted-aryl)-3-hydroxyisoindolinones with N-vinylpyrrolidone under identical conditions resulted in the formation of 2-(2-substitued-aryl)-3-(2-(2-oxopyrrolidin-1-yl)vinyl)isoindolin-1-one analogues indicating steric hinderance as the cause of deviation. The probable mechanism of the reaction based on the results from X-ray crystallography and molecular modelling is discussed.
Project description:Cellular toxicities of alpha-synuclein manifest through multiple pathways, including mitochondrial dysfunction and the inhibition of vesicle trafficking. Several defects can be ameliorated by small molecule suppressors that antagonize toxicity in model systems ranging from yeast to neurons. Connections between these distinct pathologies may be central to Parkinson Disease and to therapeutic strategies. First, yeast cultures with 1 or 2 copies of human alpha-synuclein were profiled during a time series of 0 to 6 hours. Second, to investigate any potential rescue of alpha-synuclein toxicity, one of a series of six compounds: compound 1 ((4-(3-iodophenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one); compound 2 (4-(3-bromophenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one); compound 3 (4-(5-bromo-2-fluorophenyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 4 (4-(3-bromo-4-fluorophenyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 5 (4-(4-ethyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 6 ((4R)-6-bromo-4-(4-ethylphenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one); was introduced and the expression profile assayed at 4 hours. Overall design: For the time series, at each time point (0, 2, 4, 6 hours) three yeast samples (2-copy alpha-synuclein; 1-copy alpha-synuclein; empty vector control) were each prepared and hybridized in all three combinations (2-copy vs control; 1-copy vs control; 2-copy vs 1-copy) for that time point. For the drug treatment, three yeast samples were grown each with 2-copy alpha-synuclein or an empty vector control, with or without one of six compounds: compound 1 ((4-(3-iodophenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one); compound 2 (4-(3-bromophenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one); compound 3 (4-(5-bromo-2-fluorophenyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 4 (4-(3-bromo-4-fluorophenyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 5 (4-(4-ethyl)-6,7-dimethyl-3,4-dihydro-2(1H)-quinolinone); compound 6 ((4R)-6-bromo-4-(4-ethylphenyl)-3,4-dihydrobenzo[h]quinolin-2(1H)-one). 2-color hybridization compared (a) 2-copy vs 2-copy+compound, (b) vector vs vector+compound, or (c) 2-copy+compound vs vector+compound.
Project description:IN THE TITLE COMPOUND (SYSTEMATIC NAME: 9-eth-oxy-10-meth-oxy-5,6-dihydro-1,3-dioxolo[4,5-g]isoquinolino-[3,2-a]isoquin-olin-7-ium iodide monohydrate), 2C(21)H(20)NO(4) (+)·2I(-)·H(2)O, two independent mol-ecules pack in the unit cell, where interactions between the molecules are stabilized by weak inter-molecular ?-? stacking inter-actions [centroid-centroid distances in the range 3.571?(4) to 3.815?(4)Å]. Inter-molecular C-H?O inter-actions are also observed. The iodide anions are disordered with occupancy ratios of 0.94?(1):0.06?(1) and 0.91?(1):0.09?(1). The cationic molecule is planar in structure with a small torsion resulting from the dihydropyridine ring.
Project description:Background:Pyrazolines show different biological activities. In recent years, interest in the chemistry of hydrazonoyl halides has been renewed. 1,3,4-Thiadiazoles are one of the most common heterocyclic pharmacophores with a wide range of biological activities. Results:Ethyl 2-(5-(furan-2-yl)-3-(p-tolyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-methyl-thiazole-5-carboxylate, 2-(5-(furan-2-yl)-3-(p-tolyl)-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4(5H)-one, and 1-(2-(5-(furan-2-yl)-3-(p-tolyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-methylthiazol-5-yl)ethan-1-one were synthesized from the reaction of 5-(furan-2-yl)-3-(p-tolyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide with different halogenated compounds. Thiazole, 1,3,4-thiadiazole and pyrano[2,3-d]thiazole derivatives were also synthesized. The structures of the newly synthesized compounds were elucidated based on elemental analysis, spectral data, and alternative synthetic routes whenever possible. Additionally, the newly synthesized compounds were screened for antimicrobial activity against various microorganisms. Conclusions:A new series of novel functionalized 1,3,4-thiadiazoles, 1,3-thiazoles, and pyrazoline-containing moieties were synthesized using hydrazonoyl halides as precursors and evaluated for their in vitro antibacterial, and antifungal activities. The antimicrobial results of the examined compounds revealed promising results and some derivatives have activities similar to the references used.