Cutaneous nocardiosis with discharging sinus clinically mimicking tuberculosis diagnosed by cytology.

Nocardiosis is primarily a pulmonary infection commonly seen in immunocompromised individuals. However, lymphocutaneous nocardiosis is observed in immunocompetent individuals often after trauma. The clinical and cytomorphological features of lymphocutaneous nocardiosis closely mimic the most common infections in India such as tuberculosis and mycetoma (very common cutaneous infection with discharging sinus). As it is crucial to differentiate nocardiosis from tuberculosis, to avoid unnecessary antitubercular treatment, special stains like modified Ziehl-Neelsen stain and Gram stain can be employed to differentiate the morphology of Nocardia from tuberculosis. Fine-needle cytology from these cutaneous lesions helps in yielding adequate material for rapid and accurate diagnosis of immediate specific antibiotic treatment. We report a rare case that presented with clinical diagnosis of tuberculosis but turned out to be nocardiosis on cytomorphology with simple and most feasible fine-needle aspiration method of tissue diagnosis and scrape cytology.

2-phenyl-4-bis(methylthio)methyleneoxazol-5-one: versatile template for diversity oriented synthesis of heterocycles.

4-Bis(methylthio)methylene-2-phenyloxazol-5-one (1) has been shown to be a versatile template for the synthesis of novel heterocyclic scaffolds. The key protocol involves nucleophilic ring opening of 1 with various primary aliphatic, aromatic amines and diamines to give open-chain amide adducts which are transformed into 4-bis(methylthio)methylene-2-phenyl-1-alkyl/arylimidazol-5-(4H)-ones (5) in good yields in the presence of anhydrous NaOAc/AcOH. Similarly, the amide adducts 4h-i from 3,4-dimethoxyphenylethylamine and tryptamine undergo interesting rearrangement in the presence of POCl(3) to furnish 1-(2-phenyl-5-methylthio-4-thiazolyl)dihydroisoquinoline and ß-carboline derivatives 8-9 in good yields. The amide adduct 14 from o-phenylenediamine on exposure to refluxing acetic acid or in the presence of Ag(2)CO(3) affords substituted 3H-1,5-benzodiazepinone, 2-(5-methylthio-2-phenyl-4-oxazolyl)-1H-benzimidazole and trisubstituted oxazole (15-17), whereas the bis-adduct from ethylenediamine yields ethylene bridge tethered bis-imidazole 23 and bis-oxazole 24 under similar reaction conditions. Probable mechanisms for the formation of various products have been suggested.