A Comprehensive Monograph on Molecular Hydrogen (DB15127) as an Emerging Therapeutic Agent

Section 1: Physicochemical Profile and Identification

The therapeutic potential of any small molecule is fundamentally governed by its chemical structure and physical properties. In the case of molecular hydrogen (DB15127), its identity as the simplest and lightest of all molecules dictates not only its unique biological interactions but also the significant and persistent challenges associated with its formulation, administration, and clinical application. A thorough understanding of its physicochemical profile is therefore an essential prerequisite for any critical evaluation of its role in medicine.

1.1. Chemical and Structural Identifiers

Molecular hydrogen is a small molecule classified under the DrugBank accession number DB15127 [User Query]. It is the elemental form of hydrogen, existing as a diatomic molecule with the chemical formula H2​.[1] This structure consists of two hydrogen atoms covalently bonded, each comprising a single proton and a single electron in its most common isotope, protium (

1H).[2] The simplicity of this atomic and molecular structure is a defining characteristic.

Key chemical and structural identifiers are as follows:

• Chemical Formula: H2​ [1]
• Molecular Weight: 2.01588 g/mol [1]
• CAS Registry Number: 1333-74-0 [1]
• Synonyms: Dihydrogen, o-Hydrogen, p-Hydrogen, Molecular hydrogen [1]
• IUPAC Standard InChI: InChI=1S/H2/h1H [1]
• IUPAC Standard InChIKey: UFHFLCQGNIYNRP-UHFFFAOYSA-N [1]

While protium is the major isotope, hydrogen also exists in other isotopic forms, including deuterium (2H or D), which contains one proton and one neutron, and the radioactive isotope tritium (3H or T), which contains one proton and two neutrons.[2] The name "hydrogen" is derived from the Greek

hydro genes, meaning "water former," reflecting its role in the composition of water.[2]