Sympathetic block

Reaction of dibenzylamine with ethylene oxide affords the amino alcohol, 82. Treatment of that product with thionyl chloride gives the a-sympathetic blocking agent, dibenamine (83). (Condensation of phenol with propylene chlorohydrin (84) gives the alcohol, 85. Reaction with thionyl chloride affords the chloride (86). Use of the halide to alkylate ethanolamine affords the secondary amine (87). Alkylation of this last with benzyl chloride... 

The guanidine function, when attached to an appropriate lipophilic function, often yields compounds that exhibit antihypertensive activity by means of their peripheral sympathetic blocking effects. Attachment of an aromatic ring via a phenolic ether seems to fulfill these structural requirements. Alkylation of 2,6-dichlorophenol with bromochloroethane leads to the intermediate, 58. Alkylation of hydrazine with that halide gives 59. Reaction of the hydrazine with S-methylthiourea affords the guanidine, guanoclor (60). ... 

Reaction of pyroc techol with epichlorohydrin in the presence of base affords the benzodioxan derivative, 136, (The reaction may well involve initial displacement of halogen by phenoxide followed by opening of the oxirane by the anion from the second phenolic group.) Treatment of the alcohol with thio-nyl chloride gives the corresponding chloro compound (137). Displacement of halogen by means of diethylamine affords piper-oxan (138), a compound with a-sympathetic blocking activity. 

Esterification of 136 with p-toluenesulfonyl chloride leads to the tosylate (139). Displacement of the ester with guanidine affords guanoxane (140). This drug, not surprisingly, shows peripheral sympathetic blocking activity and is therefore used in control of hypertension. 

Peripheral sympathetic blocking agent. A drug that disrupts the transmission of nerve impulses to sympathetically innervated structures. 

Sympathetic blocking agent. A drug that binds to, but does not stimulate, adrenergic receptors of the 3-type. 

Guanidines attached to a group of appropriate lipophilicity have proven to be useful antihypertensive agents, active by virtue of their peripheral sympathetic blocking activity. Debrisoguine (72) is m fact used clinically for that indication. The 7-bromo analogue (76) also shows antihypertensive... 

Table 3-2. DIFFERENTIATION OF SYMPATHETIC BLOCKING DRUGS Nictitating membrane... 

The response of the nictitating membrane may often be potentiated, depending both on the time the noradrenaline is given after the sympathetic blocking drug and on the dose of the latter. 

The basic ether of a rather more complex phenol, interestingly, exhibits a-sympathetic blocking rather than antihistaminic. ictivity. Nitrosation of the phenol derived from p-cymene (So) (lives the expected nitroso derivative (SI). Reduction (S2)... 

Sympathetic block is one use of local anesthetics. at is the best location to apply the local anesthetic ... 

Bupivacaine Marcaine, Sensor-caine Slow to Intermediate Long Infiltration Peripheral nerve block Epidural Spinal Sympathetic block... 

Lidocaine Xylocaine Rapid Intermediate Infiltration Peripheral Nerve Block Epidural Spinal Transdermal Topical Sympathetic block Intravenous regional block... 

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