Title: Orthocaine
CAS Registry Number: 536-25-4
CAS Name: 3-Amino-4-hydroxybenzoic acid methyl ester
Synonyms: methyl 3-amino-4-hydroxybenzoate
Trademarks: Orthoform (Winthrop); Orthoform New
Molecular Formula: C8H9NO3
Molecular Weight: 167.16
Percent Composition: C 57.48%, H 5.43%, N 8.38%, O 28.71%
Literature References: Prepd by dissolving 3-amino-4-hydroxybenzoic acid in methanol, saturating with HCl gas: Einhorn, Pfyl,
Ann. 311, 46 (1900);
DE 97333;
Chem. Zentralbl. 1898, II, 525. Also prepd by reduction of methyl 3-nitro-4-hydroxybenzoate with aluminum amalgam: Auwers, R?hrig,
Ber. 30, 991 (1897); with tin and HCl or with stannous chloride and alcoholic HCl:
DE 97334;
Chem. Zentralbl. 1898, II, 526.
Properties: Needles from benzene, mp 143°. When crystallized from chloroform it sometimes assumes an allotropic form, mp 111°, which on melting changes to the normal form and after solidifying always melts at 143°. Odorless and tasteless. Neutral reaction. Almost insol in cold water. Moderately sol in hot water with gradual decompn forming 3-amino-4-hydroxybenzoic acid and methanol. One gram dissolves in 6 ml alcohol, 50 ml ether; readily dissolves in aq NaOH. Forms water sol salts with HCl and HBr.
Melting point: mp 143°; mp 111°
NOTE: The name Orthoform was applied originally to the methyl ester of 4-amino-3-hydroxybenzoic acid which was also used as a local anesthetic. This compd now is designated as Orthoform Old.
Therap-Cat: Anesthetic (topical).
Therap-Cat-Vet: Anesthetic (topical).
Keywords: Anesthetic (Local).
