Antimicrobial and Antifungal Activity

As can be seen from the material presented in this review, imidazo[l,5-a]- and imidazo[l,2-a]quinoxalines arouse a great deal of interest of researchers owing to the wide range of biological activity exhibited by them. For this reason, in addition to the improvement of the known methods of their synthesis, an intensive search is carried out for new preparative procedures that afford diverse derivatives. 

Analysis of the efficiency of different methods of synthesis of imidazo[l,5-a] and imidazo[l,2-fl]quinoxalines demonstrates that there are currently 26 approaches corresponding to the retrosynthetic analysis of the stmcture of a heterocyclic system without including the benzene ring. Initial compounds are quinoxaline (see Figs. 4.3 and 4.6) or imidazole derivatives (see Figs. 4.4 and 4.7). For synthesis of imidazo[l,5-a]quinoxaline, seven approaches based on quinoxalines and four approaches based on imidazoles have been developed (Table 4.4) for synthesis of imidazo[l,2-a]quinoxalines, six approaches based on quinoxalines and five approaches based on imidazoles have been developed (Table 4.5). 

These Tables demonstrate which methods of synthesis of imidazo[l,5-a] quinoxalines are most widely used, which of them require further development, and which methods remain unused. The formation of imidazof 1,5-a]quinoxalines 107 and 108 from compounds 76 and 105, as well as the formation of imidazo[l,2-a] 

Variant Number of studies Number of stages Substituent variation positions References 

Note Here and in Table 4.5, a dash means that substituents cannot be varied 

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Caron, C., Hoizey, M. J., Le Men-Olivier, L., Massiot, G., Zeches, M., Choisy, C Le Magrex, E. and Verpoorte, R. 1988. Antimicrobial and antifungal activities of quasi-dimeric and related alkaloids. Planta Medica, 409 12. 

Abstract We report here the synthesis of newly coumarinic derivatives by using 4-hydroxy coumarine as starting material. These newly compounds were screened in vitro for their antimicrobial and antifungal activities. The structures of the synthesized compounds were proved by IR, H NMR, 13 C NMR and mass-spectral. 

El-Hashash MA, Mahmoud MR, Madboli SA (1993) A facile one-pot conversion of chal-cones to pyrimidine-derivatives and their antimicrobial and antifungal activities. Indian J Chem Sect B 32B 449 52... 

In Nigeria, fruits of V. zenkeri have been successfully used to treat lumbago and arthritis associated with different type of cancers and inflammatory diseases 48). In Cameroon, V. africana seeds extracts are used in traditional medicine to treat orchitis, tooth decay and gonorrhea, and these uses were related to the antimicrobial and antifungal activity of the extracts (7). An infusion based on the bark from V. africana has been used for the relief stomach complaints and root decoctions for hernia pain and kidney troubles (5). 

The actin antibiotics, of which several are represented by the structures 1-9, occur in various Streptomyces species (1,2). The structures were elucidated as 32-membered macrocyclic tetraesters. Nonactin itself was isolated in 1955 by Prelog and his co-workers (1) as the first member of the family, and is its lowest homologue and most symmetrical member. All members of the actin family exhibit antimicrobial and antifungal activity, which increase with increasing size of R, and insecticidal activity against mites (3). 

Kolanone (86), nemorosone II (89), propolone A (93), chamone 1 (119), and xanthochymol (138) displayed significant antimicrobial and antifungal activity against a variety of pathogenic yeasts and bacteria [72,74,77,120]. Compounds 131-134 and 138 displayed antibacterial activity against methicill in-resistant Staphylococcus aureus (MRSA) at 3.1 - 12.5 /(g/mL, nearly equal to the antibiotic vancomycin [89]. 

Hu J, ShiXD, Chen JG, Mao X.ZhuL, Yu L,etaL Alkaloids from Toddalia asiatica and their cytotoxic, antimicrobial and antifungal activities. Food Chem 2014 148 437-44. 

Angioni, A., A. Barra, W. Cereti et al., 2004. Chemical composition, plant genetic differences, antimicrobial and antifungal activity investigation of the essential oil of Rosmarinus officinalis L. J. Agric. Food Chem., 52 3530-3535. 

Toxicity seems to be an important attribute of phenols in plants. Essentially, every phenolic compound has some antimicrobial and antifungal activity (Jenkins et al., 1957 Walker, 1975). Antibiotic, antiviral, anticellular, antineoplastic, and related effects of tannins, mostly in vitroy have been reported by several researchers (Alexander, 1965 Herz and Kaplan, 1968 Kreber and Einhellig, 1972 Konowalchuk and Speirs, 1976 Chan et al., 1978 Loub et al., 1973 DeOliveira et al., 1972). 

A methanol extract of the fruits of Chinese star anise (Illicium verum) showed in vitro growth-inhibitory activity against the periodontopathic bacteria, Eikenella cor-rodens, and against the fungus Saccharo-myces cerevisiae In vitro antimicrobial and antifungal activities of Chinese star anise are largely attributed to the presence of anethole. ... 

Reported to have keratolytic and antipruritic properties and in vitro antimicrobial and antifungal activities. ... 

Quinoline incorporated benzimidazole derivatives were synthesized by Garudachari et al. [18] from substituted aniline and isatin through multi-step reaction. Final compounds were investigated for their in-vitro antimicrobial and antifungal activities by well plate method. Among the screened samples, dichlorosubstituted quinoline derivatives and nitrogene on the bezimidazole moiety showed... 

Chitosan OH >OH OH NHj NHi NHi L Jn Purified qualities of chitosans are available for biomedical applications. It is nontoxic, biodegradable, and biocompatible. Antimicrobial and antifungal activities Highly permeable to water vapor. Excellent oxygen barrier properties. Good mechanical properties. Good antimicrobial activity. 

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