This review provides a broad perspective of the uses of amino acid fluorides in the synthesis of peptides and a wide range of other molecules including peptidomimetics, heterocycles and biologically active molecules.

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Introduction: Urine cytology is an important screening tool of patients for urothelial carcinoma (UC) and follow-up of patients with treated disease. Ease of procurement, cost-effectiveness, and lower turnaround time are the major advantages. Objective: To compare current system of reporting (CSR) at our institute with The Paris System (TPS) and analyze utility of urine cytology based on TPS reporting in correlation with urine culture and histopathology. Materials and Methods: One-year retrospective study of 90 cases was undertaken wherein cases presenting with painless hematuria and clinically suspicious of UC were included. Urine cytology slides were reviewed and reported with TPS guidelines. These findings were correlated with histopathological diagnosis and urine culture as indicated. Statistical analysis was done using SPSS 17 software. Results: With TPS guidelines, 11.1% and 5.6% cases were reported as high-grade UC (HGUC) and low-grade urothelial neoplasm (LGUN), respectively. Suspicious for HGUC category included 17.8% of cases. The rate of reporting “atypical urothelial cells (AUC)” was significantly lower (11.1%) with TPS on comparison with CSR (16.7%). Histopathological correlation of positive predictive value for HGUC was better (100%) on using TPS when compared with CSR (64.3%). Among 11 cases with microbial growth on urine culture, 9.1% were reported as atypical. Sensitivity and accuracy of TPS in detecting UC were 83.3% and 86.52%, respectively. Both were higher when compared with CSR. Conclusion: In comparison to CSR, criteria of TPS limit the AUC category and enhance the sensitivity and accuracy of detecting HGUC. Adopting TPS for urinary cytology will ensure uniformity and accuracy of HGUC diagnosis.

a b s t r a c tA simple protocol for the synthesis of 2-amino-1,3,4-oxadiazoles starting from the corresponding acylhydrazides by cyclodesulfurization of intermediate acylthiosemicarbazides mediated by o-iodoxybenzoic acid in good yields has been described. The protocol is mild with wide substrate scope, and thus a range of 2-amino-1,3,4-oxadiazoles have been prepared.Ó 2012 Elsevier Ltd. All rights reserved.1,3,4-Oxadiazoles have found extensive use as pharmacophores due to their metabolic profile and ability to engage in hydrogen bonding. 2-Amino-1,3,4-oxadiazoles have a wide range of biological activities such as antimicrobial agents, anti-inflammatory agents, anticancer agents, muscle relaxants, and antimitotics, 1 the 2,5-diaryl-1,3,4-oxadiazoles are known to be platelet aggregation inhibitors.2 Due to myriad of biological applications of 1,3,4-oxadiazole scaffolds, efficient and mild methods to synthesize these moieties have attracted considerable interest. Our research group has recently reported simple access to 2-amino-1,3,4-oxadiazole peptidomimetics using p-TsCl mediated cyclization of amino acid derived thiosemicarbazides. 3 The most commonly followed strategy involves cyclization of the corresponding acyclic semicarbazide 4 (X = O) or thiosemicarbazide derivatives 5 (X = S), (Scheme 1). The reported protocols in the literature involve two steps, wherein semicarbazide/acylthiosemicarbazides were synthesized by reaction of hydrazides with the requisite isocyanate/ isothiocyanate, which is typically isolated and purified. In the following step, cyclization was carried out using an appropriate reagent. Most of these methods have several disadvantages such as handling of harsh and toxic reagents, elevated temperatures, long reaction time etc. Xie et al. has recently described an efficient cyclodeselenization by heating selenosemicarbazides (X = Se) in DMF in one-pot from isoselenocyanates and hydrazides, 6 resulting in high yields of 2-amino-1,3,4-oxadiazoles. This protocol is devoid of the usage of any deselenizing reagent. Also there are a few reports wherein one pot strategy was explored starting from acylhydrazides using p-TsCl/pyridine 5a and PS-carbodiimide 7 and both these methods suffer from harsh conditions which require heating for long hours for the cyclization of the acylthiosemicarbazide intermediate. Thus newer and mild protocols for this privileged class of molecules are continuously sought. In quest of novel methodologies for heterocycles, we have now focused on a simple and efficient protocol for the synthesis of 2-amino-1,3,4-oxadiazoles. Hypervalent iodine reagents have been extensively used in various organic transformations because of their mild oxidizing and environmentally benign nature. The iodine atom in hypervalent iodine(V) reagents has strong electrophilic character and with the leaving ability of the phenyliodino group makes them reagents of choice for various oxidative transformations.8 In addition, their affinity for sulfur has made these reagents attractive alternatives fo...

The review provides a broad overview of amino acid chlorides in peptide chemistry, classified into different sections comprising reagents, N-protected amino acid chlorides (preparation and properties), coupling employing various protocols and applications in difficult and hindered couplings. The recent developments include their applications in synthesis of various amino acid derivatives, peptidomimetics, heterocycles and biologically active molecules.

Male rats and rabbits were immunized against gonadotropin-releasing hormone (GnRH) conjugated to tetanus toxoid (GnRH10-TT) using only materials approved for humans. Testosterone (T)-releasing implants or the long-lasting T ester testosterone-17-trans-4-n-butyl-cyclohexane carboxylate (TE) was used as supplemental androgen for maintaining libido. Immunization against GnRH10-TT effectively suppressed fertility (spermatogenesis) in rats and rabbits. Neither T nor TE administration restored fertility. Both androgens were effective in maintaining normal libido in rats. TE, which is not hydrolyzed in rabbits, was less effective in maintaining normal ejaculatory behavior in this species. Active immunization against GnRH could be a convenient and cost-effective method of fertility control in males.

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Gold nanoparticles (AuNPs) of 30-40 nm in size has been prepared using A. hirsutus leaves extract as reducing agent for Au 3? ions under microwave irradiation from 60 to 360 s. These biocapped AuNPs were effectively conjugated with activated folic acid (FA, receptor) and chlorambucil (CHL, anticancer drug) molecules. The formation of AuNPs-FA-CHL was confirmed from different characterization techniques such as XRD, UV-Visible spectra, FT-IR and TEM images. The anticancer activity of these bioconjugated AuNPs was tested against human cancer cell lines (HeLa, RKO and A549) in comparison with normal epithelial cells (Vero). Unlike AuNPs and CHL alone, AuNPs-FA-CHL showed high toxicity towards human cancer cells by significantly decreasing the percentage viability of cells. Furthermore, the amount of drug released was found to be maximum at an ideal tumor environment pH 5.3.