zyklophin zyklophin zyklophin is a semisynthetic peptide derived from dynorphin a and a highly selective antagonist of the κ-opioid receptor (kor). it is systemically-active, displaying good metabolic stability and blood-brain-barrier penetration. similarly to other kor antagonists, it has been shown to block stress-induced reinstatement of cocaine-seeking in animals. the drug is currently experimental, and thus cannot be considered safe for consumption or usage. zyklophinclinical dataatc codenonelegal statuslegal status in general: legal identifiers iupac name n-benzyl-l-tyrosylglycylglycyl-n--3-(-1-pyrrolidinyl]-1-oxo-2-pentanyl}carbamoyl)-9-(3-carbamimidamidopropyl)-5,8,11,14-tetraoxo-1,4,7,10-tetraazacyclotetradecan-12-yl]-l-phenylalaninamide pubchem cid45483651chemspider30844961chemical and physical dataformulac65h96n20o13molar mass1365.610 g·mol−13d model (jsmol)interactive image smiles cc(c)1c(=o)n(cnc(=o)c(c(=o)n(c(=o)n1)cccnc(=n)n)nc(=o)(cc2=cc=cc=c2)nc(=o)cnc(=o)cnc(=o)(cc3=cc=c(c=c3)o)ncc4=cc=cc=c4)c(=o)n(cccnc(=n)n)c(=o)n5ccc5c(=o)n(ccccn)c(=o)n inchi inchi=1s/c65h96n20o13/c1-3-38(2)54-62(97)83-49(60(95)81-45(21-13-29-73-65(70)71)63(98)85-30-14-22-50(85)61(96)79-43(55(67)90)19-10-11-27-66)35-75-51(87)33-48(59(94)80-44(57(92)84-54)20-12-28-72-64(68)69)82-58(93)47(32-39-15-6-4-7-16-39)78-53(89)37-76-52(88)36-77-56(91)46(31-40-23-25-42(86)26-24-40)74-34-41-17-8-5-9-18-41/h4-9,15-18,23-26,38,43-50,54,74,86h,3,10-14,19-22,27-37,66h2,1-2h3,(h2,67,90)(h,75,87)(h,76,88)(h,77,91)(h,78,89)(h,79,96)(h,80,94)(h,81,95)(h,82,93)(h,83,97)(h,84,92)(h4,68,69,72)(h4,70,71,73)/t38-,43-,44-,45-,46-,47-,48-,49-,50-,54-/m0/s1key:uwlikqfwzopoax-klroisqlsa-n