Modafinil acid

Modafinil acid (code name CRL-40467), also known as modafinilic acid or modafinil carboxylate, is one of the two major metabolites of modafinil – the other being modafinil sulfone.^[1] Modafinil acid is also a metabolite of the modafinil prodrug, adrafinil, and the (R)-(–)-enantiomer is a metabolite of armodafinil, the (R)-(–)-enantiomer of modafinil.^[2] Between 30 - 60% of modafinil is converted to modafinil acid and its half life is roughly half that of modafinil (about 7 hours).^[3] Modafinil acid seems to be inactive,^[4] and similarly to modafinil sulfone, does not appear to contribute to the wakefulness-promoting/psychostimulant effects of modafinil.^[5][6][7]

Modafinil acid

Names
Preferred IUPAC name (Diphenylmethanesulfinyl)acetic acid
Other names Modafinilic acid; Modafinil carboxylate; CRL-40467
Identifiers
CAS Number	63547-24-0 Y
3D model (JSmol)	Interactive image
ChemSpider	2342211
ECHA InfoCard	100.219.633
PubChem CID	3085267
UNII	54N37HN7N4 Y
CompTox Dashboard (EPA)	DTXSID60979768
InChI InChI=1S/C15H14O3S/c16-14(17)11-19(18)15(12-7-3-1-4-8-12)13-9-5-2-6-10-13/h1-10,15H,11H2,(H,16,17) Key: QARQPIWTMBRJFX-UHFFFAOYSA-N
SMILES C1=CC=C(C=C1)C(C2=CC=CC=C2)S(=O)CC(=O)O
Properties
Chemical formula	C15H14O3S
Molar mass	274.33 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

In the breakdown process of modafinil, modafinil is primarily hydrolyzed by an esterase or amidase enzyme into modafinil acid.^[8] The apparent clearance of modafinil acid is significantly higher than that of modafinil, following the hypothesis that metabolism increases the polarity and the clearance of modafinil.^[9]

See also

• List of modafinil analogues and derivatives