a nicotinic cholinoreceptor antagonist at the neuromuscular junction; curare-like ganglioblocker.

Bis-quaternary quinuclidine derivative, C₂₆H₄₂Cl₂N₂O₆, synthetic.

• Molecular Weight : 549.53 Da.
  
  
• Melting Point : 182-189 °C.
  
  
• Solubility in : in water, ethanol.
  
  
• Purity min. : min. 98%.
  TLC ['Silufol UV-254', MeOH-NH3 (25%) (10:1) Rf <0.1, control by the absence of starting platinecin with Rf 0.2. Visualization with UV-light, followed with Dragendorff's reagent]; NMR (in D₂O).
  
  
• Physical Form : colorless crystal powder.
  
  
• Chemical Name : 4,4'-[m-phenylene-bis-(oxyethylene)]bis-[hexahydro-1-hydroxy-7-(hydroxymethyl)-H-pyrrolizinium dichloride; 1,1'-[b,b '-(m-phenylenedioxy)diethylene]bis-[4-hydroxy-6-(hydroxymethyl)-1-azoniabicyclo[3.3.0]octane dichloride.
  
  
• Biological Activity : Curare-form competitive anti-depolarizing muscle relaxant. Used for muscle relaxation and controlled breathing under narcosis during surgical operations. Can be used for tracheal intubation.
  
  Less potent than d-Tubocurarin. In humans i.v. 1.5-2 mg/kg causes muscle relaxation without breathing suppression; 4-5 mg/kg in 4-5 min complete myorelaxation and apnoe for 20-30 min.
  
  Gradual decurarization: after restoration of spontaneous breathing abdominal and limbs muscles relaxation for some time. To prolong the action of Diplacine the repeated dose must be 1.5-2 times lower.
  
  The effect is antagonized by Proserine.
  No histamine liberation, no laringo- or bronchoconstriction. High doses may induce 15-20 mmHg blood pressure increase.
  
  For comparative information see the attached table.
  
  
• Toxicity (LD₅₀) : mice (i.v.): 5.3 mg/kg.
  
  
• Storage recommendations : stable in dry state up to 100 °C; solutions are stable for 1-2 days. Solution for use: 10-³ M (2 mg in 3.64 ml).
  
  
• Safety recommendations : highly toxic! Do not swallow nor inhale; avoid eye and skin contact.
  
  
• CAS Reg. No. : 863-83-2
  
  
• Bibliography :
  
  1. Sadritdinov F., Farm.Toksikol (1962) (Russian). (SAR for polymethylene bis-quinuclidiniums) 25(3):327-335
  2. Mashkovsky M.D. Lekarstvennye Sredstva (Drugs) -Moscow, Meditzina, (1984). 1:260