Guanosine is a naturally occurring nucleoside found in RNA and also an important component in the synthesis of DNA. This chemical compound is made up of the purine nucleobase guanine and the sugar ribose, with a chemical structure of C10H13N5O5. 

Guanosine is commonly used in medical research as a source of guanine or as a substrate for the enzymatic reactions involved in the synthesis of nucleic acids. It is also known to have various biological activities, including stimulating neurotransmitter release in the brain, modulating blood pressure, and providing cardioprotection. 

This versatile and important compound has various pharmaceutical and biotechnological applications. In the pharmaceutical industry, it is used as a precursor to anti-viral drugs and chemotherapy agents, as well as being investigated in the development of treatments for cancer, Alzheimer's disease, and other neurological disorders. In the biotech industry, guanosine and its derivatives are used for the production of enzymes, nucleic acids, and vaccines. 

At present, guanosine is primarily sourced from yeast extract, but alternative methods of production are being explored in order to improve yields and purity. With its many applications and potential uses, guanosine is a critical component in today's medical and biotechnology research industry.