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^US Patent 4098904 - Analgesic N-(2-aminocycloaliphatic)benzamides ^'Factors Affecting Binding of trans-N-[2-(Methylamino)cyclohexyl]benzamides at the Primary Morphine receptor' B. Vernon Cheney, Jacob Smuszkovicz, Robert A. Lahtr & Dominic A. Zichi - J Med Chem. 1985 Dec;28(12):1853-64. ^Medicinal agents incorporating the 1,2-diamine functionality - Erik T. Michalson, Jacob Szmuszkovicz, Progress in Drug Research Volume 33, 1989, pp 135-149 ^US Patent 3258489 N-1(aminocyclohexyl)anilines and N-(1-nitrocyclhexylmethyl)Anilines ^US Patent 3975443 (3,4-dichlorobenzamidomethyl)-Cyclohexyldimethylamine, US Patent 3499033 Ethers of alpha-phenyl-2-aminocycloalkanemethanols ^US Patent 3510492 2-anilino and 2-anilinomethyl cycloalkylamines ^US Patent 3647804 Cycloalkanecarboxamides ^US Patent 3825595 N-cyclopentyl-n-2-hydroxyalkyl-ring-substituted benzamides ^US Patent 4049663 Ethylene Diamine Derivatives ^'Opioid Analgesics, Chemistry and Receptors' Page395 Alan F. Casy & Robert T Parfitt ISBN 0-306-42130-5 ^'Structure Activity Studies of Two Classes of Beta-Amino-Amides: The Search for Kappa-Selective' Opioids G.Loew, J.Lawson, L.Toll, G.Frenking, I.Berzetei-Gurske and W. Polgar Pages 144-151 NIDA Research Monograph Series 90 PMID 2855852 ^{'Phenanthridone} Analogs of the Opiate Agonist U-47,700 in the trans-1,2-Diaminocyclohexane Benzamide Series' Shikai Zhao, Michael J. Totleben, Stephen A. Mizsak, Jeremiah P. Freeman, and Jacob Szmuszkovicz - Heterocycles Special issue | Vol 52, No. 1, 2000, pp.325-332 Published online, 1st January, 1970 ^'U-50,488 and the к receptor: A personalized account covering the period 1973 to 1990' by Jacob Szmuszkovic, Progress in Drug Research Volume 52, 1999, pp 167-195 ^{'Differentiation} of ς, μ and ϰ opioid receptor agonists based on pharmocore development and computed physicochemical properties' Journal of Computer-Aided Molecular design, 15: 297-307, 2001