Pharmacological studies on novel basic aminoalkyl aryl ethers as potential local anesthetics

ABSTRACT

Following our previous investigations on certain new aminoalkyi aryl ethers, which showed promising and outstanding local anaesthetic properties, the local anaesthetic activity and duration of action of a further selection of four novel derivatives of the above-mentioned series, used as hydrochloride salts, have been determined by the in vivo rat sciatic nerve test. These are N N-dimethyl-2- [2,6-di-tert-butylphenoxy] ethylamine; N, N-dimethyl-2- [4-butoxyphenoxy] elhylamine; N, N-dimethyl-2- [2,6-di-.sec-butylphenoxy]ethylamine; and N, N diethyl-2-[4-sec-butylphenoxy]ethylamine. The tests have been performed by adouble blind, controlled trial [at the later stage] and in two stages. Bupivacaine hydrochloride has been employed as the standard and normal saline as the control. The complete loss of motor function of the injected limb of the animal is considered as a positive response, which is assessed by observing the animal gait and ability to climb up a sloping wire mesh. The test compounds have exhibited shorter duration of motor paralysis than that of the standard and comparable rates of both onset of action, and recovery time from full analgesia. They also have shown neither apparent systemic nor local side effects such as edema, swelling, induration, ulceration, necrosis, or irritation