Recebido em 24/8/12; aceito em 7/1/13; publicado na web em 24/5/13Four new compounds with the general formula [Fe(phen) 3 ][Zn(RSO 2 N=CS 2 ) 2 ], where phen = 1,10-phenanthroline, R = 4-FC 6 H 4 (1), 4-ClC 6 H 4 (2), 4-BrC 6 H 4 (3) and 4-IC 6 H 4 (4), respectively, were obtained by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO 2 N=CS 2 K 2 ) and tris(1,10-phenanthroline)iron(II) sulfate, with zinc(II) acetate dihydrate in dimethylformamide. The elemental analyses and the IR data were consistent with the formation of the expected complexes salts. The 1 H and 13 C NMR spectra showed the signals for the cationic iron(II) complex and dithiocarbimate moieties. The molar conductance data were consistent with the 1:1 cation:anion complexes in 1-4. The antifungal activities of the compounds were tested in vitro against Candida albicans, Candida tropicalis and Colletotrichum gloeosporioides.Keywords: dithiocarbimates; metal complexes; antifungal activity. INTRODUCTIONFungal infections in humans have increased in recent years predominantly affecting immunocompromised patients. 1,2 Fungi from the Candida genus can infect the oral and vaginal cavities, skin and, more seriously, essential organs. 1,3 Colletotrichum gloeosporioides is known to infect a wide variety of hosts, including vegetables, field and forage crops, fruit trees, and ornamental shrubs. 4 C. gloeosporioides infections in humans can cause keratitis in healthy or immunocompromised individuals and can induce phaeohyphomycosis in patients with hematologic malignancies and iatrogenic immunosuppression. [5][6][7] Several dithiocarbamate and N-substituted dithiocarbamate complexes and salts (Scheme 1a) have been used as agrochemicals mainly due to their high efficiency in controlling plant fungal diseases, and their relatively low toxicity. 8,9 The literature reports that dithiocarbamate complexes are also active against Candida spp. 10In recent studies, we have demonstrated that the dithiocarbimate compounds A 2 [Zn(RSO 2 N=CS 2 ) 2 ] and A 2 [Sn(Bu) 2 (RSO 2 N=CS 2 ) 2 ] (A = tetrabutylammonium cation or tetraphenylphosphanium cation, Bu = n-butyl and R = 4-FC 6 H 4 , 4-ClC 6 H 4 , 4-BrC 6 H 4 and 4-IC 6 H 4 ) are active against Colletotrichum gloeosporioides. 11-13 It was also observed that the cations Bu 4 N + and Ph 4 P + were inactive.Unlike dithiocarbamate analogues, the bis(dithiocarbimate) metal(II) complexes are anionic species (Scheme 1), offering potentially useful modulation of this activity. For example, enhanced antifungal activity should be possible either by the use of active counter ions, or by varying the solubility of the salts of the complexes through the use of different cations.Considering these possibilities, the activities of some salts were tested in order to find an appropriate active cation to deepen the investigation into the antifungal potential of dithiocarbimates. This search revealed that tris(phenantholine)iron(II) perchlorate is active against Colletotrichum gloeosporioides. Here we describe the s...

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4 P = tetraphenylphosphonium, R = CH 3 (1), C 2 H 5 (2) and C 4 H 9 (3); Fe(phen) 3 = tris(1,10-phenanthroline) iron(II), R = CH 3 (4), C 2 H 5 (5) and C 4 H 9 (6)] were synthetized from potassium dithiocarbimates (RSO 2 N=CS 2 K 2 .H 2 O) in reaction with dichlorobis-n-butyltin(IV) and tetraphenylphosphonium chloride (1)(2)(3) in N,N-dimethylformamide or tris(1,10-phenanthroline) iron(II) (4-6) in methanol. The new compounds were characterized by elemental analysis of Fe and Sn, and by vibrational, Mössbauer and nuclear magnetic resonance of 1 H, 13C and 119 Sn spectroscopies. High-resolution mass spectra in the negative and positive modes were also obtained. The elemental analyses and the exact masses obtained for the cations and the complex anions were consistent with the proposed formulae. The Mössbauer spectroscopic data were consistent with the presence of tin(IV) with coordination numbers between 4 and 5 (compounds 1-6), and of hexacoordinated iron(II) (compounds 4-6). The INTRODUÇÃOOs ditiocarbamatos (DTC) formam uma importante classe de ligantes aniônicos cujos complexos metálicos apresentam diversas aplicações, tais como fungicidas, aceleradores da vulcanização da borracha e como precursores sintéticos para a deposição de nanopartículas de sulfetos metálicos. Devido à dupla carga negativa dos ânions ditiocarbimato, frequentemente seus complexos são aniônicos. Isso permite uma grande versatilidade desses compostos porque o contraíon também pode ser importante para a atividade. Esse fato tem sido explorado em alguns trabalhos ficando demonstrado que a presença dos contraíons tetrafenilfosfônio e tris(1,10-fenantrolina)ferro(II) foi importante para a atividade de sais de complexos de zinco com ditiocarbimatos. 6,7 O gênero de fungos Botrytis, agente causal do mofo cinzento, é responsável por diversas doenças em plantas ornamentais, frutíferas e oleráceas. A espécie Botrytis cinerea é responsável pela podridão em culturas de importância econômica como morango, uva e tomate.8 Colletotrichum acutatum é o agente causal da podridão floral dos citrus, que afeta flores e frutos de quase todas as variedades de interesse comercial. Em morangueiros, C. acutatum é responsável pela doença conhecida como flor preta, em decorrência da secagem e escurecimento das flores nas plantas afetadas. Além das flores, lesões também atingem frutos e, ocasionalmente, o rizoma, causando murcha e morte das plantas. A podridão amarga, doença de maior importância na cultura da macieira, também é resultado da infecção por C. acutatum. 9-11Tendo em vista essas considerações, este trabalho descreve a síntese de seis novos sais com ânions complexos de dibutilestanho(IV) com ditiocarbimatos e os cátions: tetrafenilfôsfonio e tris(1,10-fenantrolina)ferro(II), de fórmulas gerais: (Ph 4 P) 2 [Sn(Bu) 2 (RSO 2 N=CS 2 ) 2 ] e [Fe(phen) 3 ][Sn(Bu) 2 (RSO 2 N=CS 2 ) 2 ] [Ph 4 P = cátion tetrafenil fosfônio, R = CH 3 (1), C 2 H 5 (2) e C 4 H 9 (3); Fe(phen) 3 = cátion tris(1,-10-fenantrolina)ferro(II), R = CH 3 (4), C 2 H 5 (5) e C 4 H 9 (6)]. Desc...