The Oxygen-Containing Fused Heterocyclic Compounds

The oxygen-containing heterocycles are an important class of compounds in organic chemistry. These compounds are used as drugs (coumarin and oxazole), solvent (tetrahydrofuran), flavors, and fragrances (lactones). The fusion of aromatic ring to the oxygen-heterocycle will change the electron density; thereby, the physical/chemical/biological properties will alter. Also, the preparation of these fused molecules will require a different strategy/method/reaction condition. The topics covered in this chapter are the general synthetic methods and uses of fused heterocyclic compounds containing oxygen as a heteroatom. The derivatization of the primary scaffold is excluded from this chapter. Some of the fused compounds are coumarin (benzopyrans) and piclozotan (benzoxazepines)

Chitosan nanoparticles as a promising tool in nanomedicine with particular emphasis on oncological treatment

Abstract The study describes the current state of knowledge on nanotechnology and its utilization in medicine. The focus in this manuscript was on the properties, usage safety, and potentially valuable applications of chitosan-based nanomaterials. Chitosan nanoparticles have high importance in nanomedicine, biomedical engineering, discovery and development of new drugs. The manuscript reviewed the new studies regarding the use of chitosan-based nanoparticles for creating new release systems with improved bioavailability, increased specificity and sensitivity, and reduced pharmacological toxicity of drugs. Nowadays, effective cancer treatment is a global problem, and recent advances in nanomedicine are of great importance. Special attention was put on the application of chitosan nanoparticles in developing new system for anticancer drug delivery. Pre-clinical and clinical studies support the use of chitosan-based nanoparticles in nanomedicine. This manuscript overviews the last progresses regarding the utilization, stability, and bioavailability of drug nanoencapsulation with chitosan and their safety