Development of a rapid and reproducible TLC method for purity elucidation and related substance identification of metronidazole in metronidazole dosage forms

Introduction: Thin-layer chromatography (TLC) is a quick, inexpensive microscale technique applicable for determination of the number of components in a mixture, monitoring the progress of an organic reaction, verification of substance identity and analysis of the fraction obtained from column chromatography.Aim: The aim of our work is to develop a rapid TLC method for related substance identification, purity elucidation, and control of synthesis of metronidazole in dosage forms and during synthesis of derivatives.Materials and Methods: A rapid and reproducible TLC method for quality determination of metronidazole derivatives is described. The samples and standard were separated on silica gel 60 with fluorescent indicator UV254 plates with three different mobile phases: A) acetic acid-ammonia-acetone-methylene chloride cyclohexane (1:2:3:3:1), B) toluene-chloroform-methanol (2:7:1), C) toluene-chloroform-ethanol-acetic acid-ammonia (9:8:1:1:1). The visualization of spots was done at 254 nm.Results: As most appropriate was established to be the mobile phase consisting of toluene- chloroform-ethanol-acetic acid-ammonia (9:8:1:1:1). The identification and determination of metronidazole in analyzed drug formulations were proved by the correspondence between the Rf of drug samples and reference standard Rf-0.58.Conclusion: The TLC method for related substance determination of metronidazole in drug formulations is an informative, rapid, and reproducible method. The method may be applied for further analysis and monitoring of synthesis of new metronidazole derivatives.

In vitro study of antimicrobial activity of essential oils of Origanum vulgare against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922

INTRODUCTION: Essential oils are aromatic and volatile liquids, extracted from different plant parts with antibacterial, antifungal, antiviral, antioxidant, and biological properties. For example, the essential oil of oregano presents antioxidant and antimicrobial activities.AIM: The aim of this study is to evaluate the potential antimicrobial activity of two (for external and internal use) commercial essential oils of Origanum vulgare against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922.MATERIALS AND METHODS: The study was conducted in Medical College, Varna, Bulgaria. The antimicrobial activity of oregano essential oils was determined by the use of the Kirby-Bauer disk diffusion susceptibility test.RESULTS: Antimicrobial activity of oregano essential oils (for external and internal use) was efficient in the control of Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. This inhibitory effect was observed by the inhibitory diameters above 21 mm.CONCLUSION: The future evaluation of natural essential oils with a relatively high in vitro activity could be researched in the treatment of various infectious diseases.

Reaction strategies for synthesis of imidazole derivatives: a review

The development of a methodical directional synthesis of complex organic molecules with the aim of obtaining the physiologically active substance with selective action takes a central position in modern synthetic organic chemistry. Imidazole derivatives are a key component in great many bioactive compounds of both natural and synthetic origin. Ðœany scientists in the field of pharmaceutical chemistry and pharmacology have been attracted to them in recent years. This is because of the exceptional chemical properties and biological activities that they demonstrate. It is a big challenge for the scientists to modify and synthesize new imidazole derivatives

Synthesis and in vitro antimicrobial evaluation of a new metronidazole derivative

INTRODUCTION: For decades there has been active work on the synthesis, identification, and exploration of heterocyclic compounds. However, the imidazole nucleus is the main scaffold in molecules with various pharmacological properties such as antibacterial, antifungal, antineoplastic, antiviral, antidiabetic, etc. This work describes a synthesis of new metronidazole amide derivative by condensation of -(2-methyl-5-nitro-1Н-imidazole-1-yl)acetic acid with 2-(diethylamino)ethyl 4-aminobenzoate (procaine). The chemical structure of the new compound was confirmed by its IR and UV-VIS spectral data and was evaluated for in vitro potential antimicrobial activity against standard bacterial strains of Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231.AIM: The present study aimed to synthesize, characterize, and evaluate the potential antimicrobial activity of a new metronidazole amide compound against standard bacterial strains of Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, and Candida albicans 10231. MATERIALS AND METHODS: The new amide metronidazole derivative 2-(diethylamine) ethyl 4-(2-(2-methyl-5-nitro-1H-imidazole-1-yl)acetamide)benzoate was tested for in vitro antibacterial activity by the following described methods: cup-plate technique, minimum inhibitory concentration determination (MIC), and minimum bactericidal concentration (MBC) determination.RESULTS: A synthesis of a new metronidazole amide derivative was made by condensation of -(2-methyl-5-nitro-1Н-imidazole-1-yl)acetic acid with 2-(diethylamino)ethyl 4-aminobenzoate (procaine). The chemical structure of the new compound was confirmed by its IR and UV-VIS spectral data and was evaluated for in vitro potential antimicrobial activity against standard bacterial strains of Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231. CONCLUSION: The obtained data assess the same antimicrobial activity of the new compound and metronidazole against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231. The highest sensitivity was observed against Candida albicans