Title: Fenbutrazate
CAS Registry Number: 4378-36-3
CAS Name: a-Ethylbenzeneacetic acid 2-(3-methyl-2-phenyl-4-morpholinyl)ethyl ester
Additional Names: 2-phenylbutyric acid 2-(3-methyl-2-phenylmorpholino)ethyl ester; 2-(3-methyl-2-phenylmorpholino)ethyl 2-phenylbutyrate; phenbutrazate
Molecular Formula: C23H29NO3
Molecular Weight: 367.48
Percent Composition: C 75.17%, H 7.95%, N 3.81%, O 13.06%
Literature References: Prepn: H. Siemer, O. Hengen, US 3018222 (1962 to Ravensberg). Physical properties and pharmacology: O. Hengen, H. Siemer, Arzneim.-Forsch. 5, 526 (1955).
Properties: Honey colored, viscous oil, bp0.05 235-240°. Sol in methanol with neutral reaction.
Boiling point: bp0.05 235-240°
Derivative Type: Hydrochloride
CAS Registry Number: 6474-85-7
Manufacturers' Codes: R-381
Molecular Formula: C23H29NO3.HCl
Molecular Weight: 403.94
Percent Composition: C 68.39%, H 7.49%, N 3.47%, O 11.88%, Cl 8.78%
Properties: Crystals, mp 154°. Slightly sol in water; sol in ethanol, acetone. Practically insol in ether, benzene. LD50 in mice (mg/kg): 3200 orally; 2800 s.c. (Hengen, Seimer).
Melting point: mp 154°
Toxicity data: LD50 in mice (mg/kg): 3200 orally; 2800 s.c. (Hengen, Seimer)
Derivative Type: Hydrochloride mixture with phenmetrazine theoclate
CAS Registry Number: 8004-38-4
Trademarks: Cafilon (Ravensberg); Filon (Berk)
Therap-Cat: Anorexic.
Keywords: Anorexic.
Fencamfamine Fencamine Fencibutirol Fenclozic Acid Fendiline

Systematic (IUPAC) name
2-(3-methyl-2-phenylmorpholin-4-yl)ethyl 2-phenylbutanoate
Clinical data
Legal status Prescription only
Routes Oral
CAS number 4378-36-3
ATC code None
PubChem CID 20395
ChemSpider 19210
UNII BKY8H56395 YesY
Chemical data
Formula C23H29NO3 
Mol. mass 367.48 g/mol

Fenbutrazate (INN), also known as phenbutrazate (BAN), is a psychostimulant used as an appetite suppressant under the trade names Cafilon, Filon, and Sabacid in Europe, Japan, and Hong Kong.[1][2] It is a derivative of phenmetrazine and may function as a prodrug to it similarly to phendimetrazine.[3] It is not known to be a controlled substance anywhere in the world yet.