17-Aralkyl-6 beta-azido-4,5 alpha-epox-ymorphinan-3-01{hu s
United States Patent [1 1 Melt zer [4 1 Apr. 29, 1975 17-ARALKYL-6 BETA-AZlDO-4,5  
 ALPHA-EPOXYMORPHINAN-3-OLS [75] Inventor: Robert I. Meltzer, Rockaway, NJ.  
 [73] Assignee: Warner-Lambert Company, Morris Plains, NJ.  
 [22] Filed: Aug. 31, 1973 [21] Appl. N0.: 393,378  
 [52] U.S. Cl 260/285; 424/260 [51] Int. Cl. CO7D 43/28 [58] Field of Search 260/285 [56] References Cited UNITED STATES PATENTS 5/1967 Brown ct al. 260/285 Primary Examiner-Donald G. Daus Assistant E \&#39;aminer-Mary Vaughn Allvrney, Agent, or FirmAlbert H. Graddis; Frank S. Chow [57] ABSTRACT The present invention relates to novel l7-araIkyl-6B- azido-4,5a-epoxymorphinan-li-Ols having the following structural formula:  
 in which R is phenyl lower alkyl such as, for example phenethyl. These compounds are useful as analgesics and antitussive agents.  
 2 Claims, No Drawings 1 l7-ARALKYL-6-BETA-AZIDO-4,5  
 ALPHA-EPOX-YMORPHINAN-3-0l The present invention relates to novel morphine derivatives and, more particularly, the present invention relates to l7-aralkyl-6B-azido-4,5a-epoxymorphinan- 3-ols having the following structural formula:  
 wherein R is phenyl lower alkyl in which lower alkyl has 1 to 7 carbon atoms.  
  The present invention also includes within its scope pharmaceutically acceptable acid addition salts of these novel azidomorphine derivatives.  
  The compounds of this invention are useful as analgesics and antitussive agents. They are administered parenterally or orally for the management of pain in any of the usual pharmaceutical forms including tablets, capsules, powders, suspensions, solutions, syrups and the like. Particularly valuable formulations include sustained release preparations which may be compounded by any of the known procedures. Generally these compounds are effective in effecting analgesia at a dosage of from about 0.1 to about 0.5 mg. per kg. of body weight. As with any analgesic agent, the dosage should be adjusted to the severity of the indication and the degree of response. Moreover the dose may be repeated as appropriate depending upon the nature of the particular formulation, the response and the condition of the patient.  
  According to the present invention the above compounds are prepared by acylating 4,5a-epoxy-morphinan-3,6oz-diol, e.g., with phenyl alkanoyl chloride. The l7-acylated product is reduced with a complex metal hydride to obtain 4,5ot-epoxy-l7-R -3,6a-diol. This is reacted with tosylchloride or mesylchloride to give, e. g. 4,5 a-epoxy-3,6a-ditosyloxyl 7-R -mrphinan, followed by treatment with sodium azide to yield 6B- azido-4,5a-l7-R -3-tosyloxymorphinan. The com pounds of this invention are obtained by alkaline hydrolysis of the latter product.  
  The starting material is disclosed in Ber., 49, 750 (1916).  
  A further embodiment of the present invention includes the acid addition salts prepared from pharmaceutically acceptable non-toxic acids. Such pharmaceutically acceptable non-toxic acid addition salts include those derived from organic and inorganic acids such as, without limitation, hydrochloric, hydrobromic, sulfuric, phosphoric, methanesulfonic, acetic, lactic, succinic, malic, maleic, aconitic, phthalic, tartaric, embonic and like acids.  
  In order to further illustrate the practice of this invention, the following examples are included:  
 EXAMPLE 1 Preparation of 4,5a-Epoxyl 7-phenacetylmorphinan3,6a-diol To a suspension of 18 g 4,5a-epoxymorphinan-3,6adiol* in 330 ml methanol and ml water is added 33.3 g of potassium carbonate. This is followed by 32.2 g of phenylacetyl chloride which is added over a 10 minute period, maintaining a temperature of about 25C. The resulting mixture is stirred an additional 3 hours, diluted with 2 1. water and extracted with three 1 1. portions of ethyl acetate. The combined extracts are washed with two 200 ml portions of 1.67 N hydrochloric acid followed by 200 ml of water, dried, filtered and the solvent evaporated. Tetrahydrofuran is added and the solvent is again evaporated. The resulting residue is reduced without further purification as described in example 2.  
 *This product is disclosed in Von Braun and Kindler Bcr., 49, 750 (1916).  
 EXAMPLE 2 Preparation of 4,5a-Epoxyl 7-phenethylmorphinan-3 ,6a-diol To 25.7 g of crude 4,5a-epoxy-l7-phenacetylmorphinan-3,6a-diol is added ml of ether. A solution of lithium aluminum hydride in 300 ml ether is added cautiously and the mixture is refluxed for 16 hours. The reaction mixture is chilled and 750 ml of 17% hydrobromic acid are slowly added. The gum formed is isolated by decanting, filtering, mixing with methanol, and refiltering. Concentrated ammonia is added until precipitation is complete. The product is filtered and dried to give 14.5 g melting at 23 l23l.5C.  
 EXAMPLE 3 Preparation of 4,5a-Epoxy-3 ,6a-ditosyloxyl 7-phenethylmorphinan To 3.77 g of 4,5a-epoxy-l7-phenethylmorphinan- 3,6a-diol is added 30 ml pyridine. To this solution is then added 4.19 g of tosyl chloride in 30 ml pyridine over a 10 minute period. The temperature is maintained at 0C during the addition and for a further 2 hours, then brought to 25C for 16 hours. The solvent is removed under vacuum and the residue slurried in a mixture of ether, water and sodium bicarbonate until dissolved. The layers are separated and the water extracted with fresh ether. The combined ether extracts are washed with water, dried over magnesium sulfate, and evaporated to a residue of 5.5 g of an oil. This crude material is used as is in the reaction with sodium azide described in Example 4.  
 EXAMPLE 4 Preparation of 6B-Azido-4,5a-epoxyl 7-phenethyl-3- tosyloxymorphinan The 5.5 g of crude 4,5a-epoxy-3,6oz-ditosyloxy-l7- phenethylm&#39;orphinan are stirred with 120 ml of dimethylformamide, 8.06 g of sodium azide, and 19 ml of water and heated at 100C for 16 hours. After cooling, it is poured into water and extracted with four 400 ml portions of ether. The combined ether extracts are washed with water, dried and evaporated to give 4.0 g of a crude oily residue.  
 EXAMPLE 5 Preparation of 6B-Azido-4,5a-epoxyl 7-phenethylmorphinan-3ol To 4 g. of crude 6/3-azido-4,5a-epoxy-l7-phenethyl- 3-tosyloxymorphinan obtained in example 4 are added 50 ml of ethanol containing 3 ml of 50% sodium hydroxide solution. The reaction is then heated 20 minutes on a steam bath. The alcohol is removed and 50 ml of water is added. Saturated sodium bicarbonate is then added until precipitation is complete. The reaction is filtered, the solids shaken in 75 ml ether, refiltered and the ether evaporated. The residue is recrystallized from 20 ml ether, giving 0.9 g. of solid showing two major compounds on a silica gel thin layer chromatography plate. The more rapidly migrating component is isolated by column chromatography on silica gel using methanol-benzene as an eluent. One recrystallization from ether gives 300 mg. of the above named compound, melting at l39l42C. There is a strong infrared band at 2090 cm&#34;. [011 170.4C. (C=l in DMF) Calcd: C, 71.62; H, 6.51; N, 13.92.  
 Found: C, 71.09; H, 6.92; N, l4.03.  
 I claim: 1. A compound of the formula:  
 wherein R is phenyl lower alkyl in which the lower alkyl portion has 1 to 7 carbon atoms and the pharmaceutically acceptable acid addition salts thereof.  
  2. A compound according to claim 1 wherein said phenyl lower alkyl is phenethyl.