7-Methylxanthine

7-Methylxanthine (7-MX), also known as heteroxanthine, is an active metabolite of caffeine (1,3,7-trimethylxanthine) and theobromine (3,7-dimethylxanthine).^[1][2] It is a non-selective antagonist of the adenosine receptors.^[1][2] The compound may slow the progression of myopia (nearsightedness).^[1][2] It is under investigation for this purpose in children with myopia.^[1][2]

7-Methylxanthine

Clinical data
Other names	7-MX; 7-Methylxanthin; Heteroxanthin; Heteroxanthine; NSC-7861
Identifiers
IUPAC name 7-methyl-3H-purine-2,6-dione
CAS Number	552-62-5
PubChem CID	68374
ChemSpider	61660
UNII	E9M81NJM6G
KEGG	C16353
ChEBI	CHEBI:48991
ChEMBL	ChEMBL321248
CompTox Dashboard (EPA)	DTXSID60203696
ECHA InfoCard	100.008.200
Chemical and physical data
Formula	C6H6N4O2
Molar mass	166.140 g·mol−1
3D model (JSmol)	Interactive image
SMILES CN1C=NC2=C1C(=O)NC(=O)N2
InChI InChI=1S/C6H6N4O2/c1-10-2-7-4-3(10)5(11)9-6(12)8-4/h2H,1H3,(H2,8,9,11,12) Key:PFWLFWPASULGAN-UHFFFAOYSA-N

It is shown that systemic treatment with 7-MX appears to be efficient in retarding axial elongation and myopia progression among myopic children. The treatment is safe and without side effects, and may be continued until 18–20 years of age, when age-related cross-linking of collagen prevents further elongation of the eye.^[3] Additionally, further studies show that oral intake of 7-MX was associated with reduced myopia progression and reduced axial elongation in this sample of myopic children from Denmark. Randomized controlled trials are needed to determine whether the association is causal.^[4]