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The 1,8-naphthyridine core is a versatile template for drug discovery and deserves special attention because of their interesting complexation properties and medical uses. On the other hand, has been recognized that attachment of a trifluoromethyl group into heterocycles can be used to modulate the physical, chemical and biological properties. Furthermore, there are many chlorinated heterocycles that have important pharmacological activities such as example Clomacran, Chloroquine and Amodiaquine. In addition, reactions of chlorinated heterocycles with heteraromatic amines can attract specific interest to provide a synthetic route to aza-heterocycles. We have been engaged to establish protocols for regioselective cyclocondensation reactions of the type C-C and / or C-N from of a variety of β-alkoxyvinyl trifluoromethyl ketones (1) with 2,6-diaminopyridine (2,6-DAP) as well derivatization reactions from of the free amino group.

The introduction of halogenes and halogenated groups in organic molecules promotes significant changes in their chemical, physical and biological properties 1 . Halogenation reactions at position 5 of uracils and pyrimidinones has been applied to obtain new substances with biological, industrial and commercial concern. 2,3 As the examples we cited Bromacil (I)(Herbicide) and 5-Fluorouracil (II)(Antitumor) 4 (Figure 1). Furthermore, 5halouracilas can be used as synthetic intermediates in coupling reactions. 5

The synthesis of fluoroorganic compounds is a challenging topic of the modern organic chemistry. Specially, the presence of trifluoromethyl moiety in the target molecule often results in significant changes of its physical, chemical and biological properties. In addition, chromenones are not only important biologically active compounds and natural products but also valuable substrates for the synthesis of related pharmacologically interesting compounds. In this context, we decided to study the oxidative aromatization of a series of trifluoromethylsubstituted chromenones, which we had been previously synthesized in our laboratory. Considering the importance of the heterocyclic precursors 1 and product 2 3,4 the aim of this work is to report the synthesis of series of high substituted chromane derivatives from the 2-trifluoromethyl-2Hchromenones (1) employing iodine/alcohol as an efficient and selective oxidative medium with microwave (MW) irradiation procedure.

Pyrazoles derivatives has been extensively explored by our research group contemplating their biological activities. 1 Efficient approaches to introduce a CF3 group at the C-3 position of pyrazole ring in a regioselective manner has been getting attention, mostly because these compounds often show pharmacological activities such as the antiinflammatory Celecoxib ® and the anticoagulant Razaxaban ® and the anticoagulant Razaxaban ® . So, we report an efficient and regioselective insertion of a CF3 group into pyrazole rings from the reaction of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF3C(O)CH =CR 1 (OR) where R = Me or Et, R 1 = H, Me, Ph, 2-Furyl and R 1 -R 2 = -C4H8-] (1a-e) and 1-phenylsemicarbazide (2) in order to obtain 3-trifluoromethyl-1-phenylpyrazoles (3a-e) as the main isomer.

Pyrimidine are heterocyclic compounds which display a wide range of biological activities and thus have been a point of attraction in the eyes of synthetic organic chemists due to their us as potential pharmacophores.1 As part of our growing interest in the synthesis of heterocyclic compounds and in conection with the reactivity of unsymmetrical enamino diketones in cyclocondensation reactions with different bisnucleophiles, we describe herein the synthesis of a new series of polyfunctionalized 2amino-pyrimidines under thermal heating and microwave irradiation.

Homoallylic alcohols are high featured in synthetic procedures to the build of many biologically active molecules, such as macrolides, polyhydroxylated natural products, and polyether antibiotics. To access these versatile synthons, the insertion of allylic organometallics to carbonyl compounds are one of the most remarkable tools found in the literature. Besides homoallylic alcohols, triazoles also show several applications in many branches of modern chemistry, like pharmacological and agriculture field. Thus, in view of importance of the cited compounds, the aim of this work is to report the results obtained from insertion of allyl aluminum compounds to 5-alkyl(aryl)-1-(2,6-difluorobenzil)-4trihaloacetyl-1H-1,2,3-triazoles.

Octahydrochromens are compounds that contain a non-aromatic cyclic ether nucleus of tetrahydropyran, which are part of a wide array of natural compounds, as well as synthetic flavors substances. For this reason, there is a clear growth in the employing of some of them as flavor and perfume compounds in certain odorants. On the other hand, the reducing agent sodium borohydride is commonly used for reduction of unsaturated carbonyl compounds, is becoming a standard method in both academic and industrial laboratories. In this context, we describe a synthesis of a new series of substituted octahydrochromenone derivatives (2) from the 2-trifluoromethyl-2Hchromenones (1) and one example of 3,4-dihydro2H-chromane (4) from the respective 2(trifluoromethyl)chromane (3), employing sodium borohydride/ethanol as an efficient, straightforward and selective reductive reaction medium for these types of heterocyclic compounds.

Some methodologies for the synthesis of Celecoxib have been described, but often resulting an isomeric mixture of pyrazoles (1,3and 1,5-substituited) difficult to separate. 4-alkoxyvinyl trifluoromethyl ketones are important precursors blocks. From these ketones is possible to synthesize a series of heterocycles, including pyrazoles 3 and, therefore, this work aims to regioselective synthesize a series of 1,3and 1,5substituted sulfamidophenyl pyrazoles.

Compounds containing the –CO–N(R)–CO– function have shown a variety of important pharmacological properties, particularly acting as anticonvulsants. On the other hand, quinoline ring systems deserve special interest. We can also highlight that the class of five-membered heterocycles as oxazolidinones, pyrrolidin-2,5-diones and thiophenes derivatives attract considerable attention due to the broad range of pharmacological properties and their chemical applications. So, considering the great biological importance and employment of amino-heterocycles as starting material for the synthesis of new heterocycles, the purpose of this work is to report the results of an investigation of the chemical behavior of 7-amino-8-methylquinolines in side chain N-acylation and C-oxidation reactions.

Among five-membered aromatic heterocycles, 1,3,4oxadiazoles are important class of aromatic heterocycles displaying a broad spectrum of biological activities, such as antimicrobial, antiinflammatoy, analgesic, anticonvulsivant, antihypoglycemic. 1 Compounds containing oxadiazole moieties have been described as possessing anticancer or muscle relaxant activity and have been used as fluorescent whiteners. 2 Usually, the synthesis of non-symmetrical 2,5-disubstituted 1,3,4oxadiazoles has mainly been done by dehydratation of diacylhydrazines or oxidative cyclization of aldehyde N-acylhydrazones, but many other reagents and reaction conditions have been reported to achieve their obtainment.