NZ186851A

NZ186851A - Glycosyloxy derivatives of milbemycin and parasiticidal compositions

Info

Publication number: NZ186851A
Application number: NZ186851A
Authority: NZ
Inventors: M H Fisher; R L Tolman
Original assignee: Merck & Co Inc
Priority date: 1977-04-11
Filing date: 1978-04-03
Publication date: 1984-12-14
Also published as: AU3476078A; FR2387231A1; AU517287B2; JPS5435293A; FR2387231B1; GB1579118A

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number 1 86851 NEW ZEALAND PATENTS ACT, 1953 No.: Date: COMPLETE SPECIFICATION "CHEMICAL PROCESSES AND PRODUCTS' X*/we, MERCK a CO., INC., a corporation duly organised and existing under the laws of the State of Hew Jersey, United States of America, of 126 East Lincoln Ave., Rahway, State of Hew Jersey, United States of America hereby declare the invention for which ik / we pray that a patent may be granted to3fHKS/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - - 1 -(followed by page la) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 • 1 QJkB 5 1 TITLE OF HID INVENTION Carbohydrate Derivatives of Milbemycin and ProoGooca Therefor ABSTRACT OF THE DISCLOSURE Carbohydrate derivatives of the antibiotic substance milbemycin, also identified as B-41, and of 13-hydroxy milbemycin are prepared. The carbohydrate groups are attached to the available hydroxy groups of milbemycin and to the hydroxy group synthesized at the 13-position. The reactions may be made selectively such that more than one carbohydrate group may be attached to a single position, or that multiple carbohydrate groups may be attached at different positions on the molecule. The described carbohydrate derivatives have antiparasitic activity. BACKGROUND OF THE INVENTION Milbemycin, or B-41, is a substance which is isolated from the fermentation broth of a milbemycin 3 producing strain of Streptomyces. The microorganism, the fermentation conditions, and the isolation procedures are more fully described in U.S. Patent 3,950,360 and U.S. Patent 3,984,564. The structures of seven of the thirteen milbemycin compounds are described in said patents and the structures of all thirteen compounds are described in the Journal of .Antibiotics 29 (6) June 1976 pages 76-35 to 76-42 and pages 76-14 to 76-16. The milbemycin compounds described in said patents do not have any carbohydrate groups substituted thereon. - la - • t 86&5J 1 SUMMARY OF THE INVENTION 2 The carbohydrate derivatives of milbemycin 3 and 13-hydroxy milbemycin are prepared by various 4 procedures, and such compounds have been found to 5 be active antiparasitic agents. Such carbohydrate 6 derivatives are prepared by using one of several 7 reactions. The classical Koenigs-Knorr reaction is 8 successfully employed as are the silver triflate (silver 9 trifluoromethylsulfonate) modification and the Helferich 10 modification, and the reaction utilizing orthoester 11 intermediates. Thus, it is an object of this invention to 12 describe the carbohydrate derivatives of the milbemycin 13 compounds and of the 13-hydroxy milbemycin compounds. A 14 further object is to describe the processes employed to 15 prepare such carbohydrate derivatives. A still further 16 object is to describe the antiparasitic uses of such compounds. 17 Further objects will be apparent from reading the 18 following description. 19 The milbemycin compounds were originally named 20 as B-41 compounds and given the nomenclature A^, AA^, 21 A^, B^, B£, B^, C1 and CLater, however, four additional 22 milbemycin compounds were isolated from the fermentation 23 broth and the structures of all thirteen compounds 24 determined. The series was then named as milbemycin and 25 the nomenclature was changed to to and to 0^, 26 recognizing the two basic structural differences between 27 the two series of compounds. The following structural 28 formulae and tables fully describes the milbemcyin 29 compounds and the relationship between the old and new 30 nomenclature. -2- *5 1 MilbeirtV' cin R 5L h R _5 B-41 2 al h h ch3 CT3 -oh A3 3 a2 h h ch3 ch3 -och3 B2 4 a3 h h c2h5 ch3 -oh A4 5 a4 h h C2H5 ch3 -och3 B3 6 a5 -oh 0 ch- 11 L -oc-ct-c4h9 ch3 ch3 -oh A2 7 a6 -oh - -0c-ch-c4hg ch3 ch3 -°CH3 31 a 7 0 ch, II 1 3 8 -oh - -oc-ch-c h„ 4 9 0 ch, II 1 3 c2h5 ch3 -oh 9 a8 -oh " •ooch-c4h9 c2h5 ch3 -och3 .0 o a9 h h ch3 -ch2-0- o 1 B -oh ci a10 h h c2h5 -ch2oi:4^il -oh c2 I h -3- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 r O 00 j5 i 16 Q 3.3—tA Milbemycin h h. b-41 (—1 ca ch3 -och3 -ch20h Al e2 c2h5 -och3 -CHjoh co. ct3 -oh -ch3 The 13- hydroxy milbemycin compounds may be prepared from the milbemycin compounds which are unsubstituted at the 13-position) by allylic bromination with N-bromosuccinimide followed by treatment with an alkali metal alkanoate such as sodium acetate, and finally by removing the alkanoyl group by hydrolysis. This process affords the 13-hydroxy group which is then available for substitution with the below described carbohydrate groups. In the above formulae and in the 13-hydroxy milbemycin compounds, at various times, there are found hydroxy groups at the 5, 13 and 22 positions and on the methyl group at the 8 position of formula II. Any one or more of these hydroxy groups may be substituted with a carbohydrate, or sugar noiety i(also known as a glycosyl group) to form the compounds of this invention. Such compounds are more precisely defined in the following 18685 1C012 IA 1 wherein R is hydrogen or a sugar (glycosyloxy) moiety and 2 , ^2' R3' R4 ant^ R' are defined as follows: 3 h. h. h T? 11 4 e h ch3 ch3 h 5 h h ch3 ch3 6 h h c2h5 ch3 h 7 h h c2h5 ^3 8 -oh or sugar 0 ch, ii 1 3 -o-c-ch-C4H9 ch3 ch3 h 9 -oe or sugar 0 ch, ii 1 3 -0-c-ch-c4hg 0 ch, || | 3 ct3 ch3 10 -oh or sugar -0c-ch-c4h9 c2es ce3 h ch. CH. H or sugar CH. H or sugar 11 -OH or sugar 0 ch, (I I 3 -oc-ch-c^h^ c2h5 ch3 ch- 12 H CT3 -CHjOC-n^JJ H or sugar 13 H C2H5 -cHjOC-Q H 01 sugar a 1 2 3 4 5 6 7 8 9 10 11 1 868 5 1 14012 ia r"H2C wherein R is hydrogen or a sugar (glycosyloxy) moiety and R2, R' and R" are defined as follows: h. ch. c2h5 ch, rj_ ch3 ch3 h or sugar IT -OH or -O-sugar -OH or -O-sugar H provided that in the first of the above structural formulae at least one of R, R^ and R' is a sugar moiety and in the second of the above structural formulae at least one of R, R', and R" is or contains a sugar moiety. -6- 1 868 5 1 ■ rsnr? ta. 1 The nature of the sugar moiety in the above sugar 2 containing groups is not critical and any sugar may be 3 substituted onto the milbemycin substrate using the 4 procedures described below. The preferred sugar moieties 5 are glucopyranosyl, galactopyranosyl, mannopyranosyl, 5 maltosyl, arabinopyranosyl, lyxopyranosyl, xylopyranosyl, 7 ribopyranosyl, oleandrosyl, rhamnopyranosyl, fucopyranosyl, g lactosyl, ribofuranosyl, mannofuranosyl, glucofuranosyl, 9 arabinofuranosyl, mycarosyl, cladinosyl, desosaminosyl, 10 daunosaminosyl, mycaminosyl, and the like. 11 The foregoing sugars are available generally in 12 the D or L configuration. The instant invention includes 13 both of the possible configurations for attachment to the 14 milbemycin substrate. 15 The above carbohydrate or sugar groups may be 16 substituted on the milbemycin or 13-hydroxy milbemycin 17 compounds as mono, di or tri-saccharides wherein one of the 18 above sugar groups is further substituted with 19 another of the same or different sugar. In addition, 20 where there is more than one hydroxy group available for 21 substitution, the sugar groups may be present on only 22 one or on more than one of such hydroxy groups, and 23 the substitution may be with identical or different 24 sugar moieties. 25 The preferred sugar substituents are mono- or 26 disaccharide substitution with glucopyranosyl, 27 rhamnopyranosyl, oleandrosyl or daunosaminosyl groups. 2g The most preferred groups are glucopyranosyl and 29 oleandrosyl. -7- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 1 868 5 1 16012 I.V- The processes for the substitution of the carbohydrate groups are substituted onto the hydroxy groups of the substrate molecule using the Koenigs-Knorr process, the silver triflate process or the orthoester process. The carbohydrate starting materials employed for the Koenigs-Knorr, the Helferich modification thereof and the silver triflate processes are protected by acylating all of the free hydroxy groups. The preferred protecting group is the acetyl group, however, other groups such as the benzoate may be employed. The processes for the blocking of the hydroxy groups are well known to those skilled in the art. The acetyl blocking groups are also easily removed at the completion of the reaction by catalytic hydrolysis, preferably base-catalyzed hydrolysis such as with an alcoholic ammonia solution. The Koenigs-Knorr and silver triflate processes use as starting materials the acetohalo-sugars such as the appropriate acetobromohexoses and acetobromopentoses of the sugar groups listed above. The bromine atom is substituted on a carbon atom adjacent to an acetyl group and the sugar moiety becomes bonded to the substrate at the carbon atom to which the halogen was attached. In the Koenigs-Knorr reaction the milbemycin compound is dissolved under anhydrous conditions in an aprotic solvent. Ether is the preferred solvent, however, methylene chloride, acetonitrile, nitromethane, dimethoxy ethane and the like may also be employed. To the substrate solution is added the acetohalosugar -8- 1 2 3 4 5 6 7 S 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 • 1 868 5 1 16012 IA and silver oxide. A single molar equivalent of the sugar is required, however, an addition 1 to 3 moles occasionally aids the reactions, however, molar excesses beyond 3 tend to make the isolation of the product more difficult. It has been found preferable to employ freshly prepared silver oxide for the reaction, since the material tends to lose its catalytic efficiency upon standing for prolonged periods. The silver oxide is prepared from silver nitrate using known procedures. The reaction may be carried out at from 10-50°C, however, reaction at room temperature is preferred. The reaction generally requires from 2 to 10 days for completion. Reaction progress is monitored by taking aliquots from the reaction mixture and examining them with thin layer chromatographic techniques. Possible side reactions are avoided by carrying out the reaction in the dark, and this method is preferred. The product is isolated using techniques known to those skilled in the art. In one modification of the Koenigs-Knorr reaction, known as the Helferich modification thereof, a mercuric halide, such as mercuric chloride or bromide, alone or in combination with mercuric oxide or mercuric cyanide is substituted for the silver oxide. The above described reaction conditions may be employed except that nitromethane and benzene are the preferred solvents and reflux temperature is the preferred reaction temperature. -9- # 1 868 1/-A1 n M£LL2__LA 1 The silver triflate reaction uses the 2 reagent silver triflate (silver trifluoromethyl 3 sulfonate) and the acetohalosugar in the same solvents 4 listed above, with ether being preferred. The silver 5 triflate is best if highly purified and prepared fresh 6 just prior to its use. Methods for the preparation of 7 silver triflate are well known to those skilled in the 8 art. All of the reactants are combined in the solvent 9 and the reaction conducted at from 10 to 50°C for from 10 2 to 48 hours. Generally, however, the reaction is 11 complete in about 24 hours at room temperature. The 12 progress of the reaction may be followed by thin layer 13 chromatography techniques. Again the reaction is 14 preferably carried out in the dark, and with absolutely 15 dry reactants and equipment. 16 A single mole of the sugar is required, 17 however, a single molar excess is often used to aid 18 in the course of the reaction. 19 During the course of the reaction a mole of 20 triflic acid (trifluoromethanesulfonic acid) is 21 liberated. This is a very strong acid and a molar 22 equivalent of a base is required to neutralize 23 the acid. Preferred bases are non-nucleophilic bases 24 such as tertiary amines, preferably triethylamine, 25 diisopropylethylamine, diazabicycloundecane, 26 diazabcyclononane and the like. Since triflic acid is 27 such a strong acid, if the base used is not a strong 28 enough base to netutralize all of the acid, the 29 residual acid will adversely affect the course of the 30 reaction and of the isolation of the product. The -10- • 1 868 5 ICO 12 IA 1 product is isolated using techniques known to those 2 skilled in the art. 3 The orthoester process prepares sugar 4 derivatives of the milbemycin compounds from ortho- oO- (W I +o s~ OartooA ccfoinS 5 esters of a lower alkanol^and of the above sugars at 6 the hydroxy function of said milbemycins. The ortho 7 esters are prepared from the acetohalosugars using 3 a loweralkanol and procedures which are well known to 9 those skilled in the art. The reaction is carried out 10 in an aprotic solvent such as dichloroethane, 11 nitromethane, methylene chloride, dimethoxy ether, 12 acetonitrile, tetrahydrofuran and the like. Dichloro- 13 ethane, nitromethane, dimethoxy ethane and tetrahydrofuran 14 are preferred. The reaction is preferably carried out 15 at the reflux temperature of the reaction mixture and 16 is generally complete in from about 4 to 24 hours. 17 Catalytic amounts of mercuric bromide or mercuric chloride 18 are added to aid in the reaction. During the course of 19 the reaction one mole of the alcohol used to make the 20 orthoester is liberated. Thus, the preferred method 21 is to azeotropically distill off the solvent to remove 22 the alcohol and to force the reaction to completion. To 23 prevent any volume reduction, fresh solvent is 24 added as the distillation proceeds to maintain a constant 25 volume. To isolate the product, the solvent is generally 26 removed and the residue washed with a reagent to remove 27 the mercury salts, such as aqueous potassium iodide. The 28 product is then isolated using known techniques. 29 Where there is more than one position with 30 a hydroxy group which is susceptable to reaction (the -11- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 ( r 18685! 8 ICO 12 IA 7-position tertiary hydroxy has been found to be less reactive toward substitution with a sugar moiety than the others), selective substitution may be obtained by careful ordering of the reaction steps. For example the sugar reactions may be carried out on the 13-unsubstituted milbemycin and then the reactions required to prepare the 13-hydroxy may be carried out. Further glycosylation reactions may then be carried out on the 13-hydroxy-5-glycosyloxy milbemycin to prepare a compound with different sugar groups at the 5- and 13-positions. Alternatively selective acylation of one of the hydroxy groups may be used to direct the glycosylation to another hydroxy group. If the 13-glycosyloxy milbemycin is desired, the 5-hydroxy would be protected by acylation thereof, using known techniques and standard acylation reagents such as acid halides, anhydrides and the like. Then the 13-hydroxy group would be prepared and the glycosylation reactions carried out. The desired product would then be prepared by simple hydrolysis of the 5-acyl group. v groups at the 22 and 13 positions and processes for selectively glycosylating these compounds would follow a procedure similar to that employed for glycosylating compounds at the 5 and 13 positions. The milbemycin a,. and compounds have hydroxy groups at the 5 and 22 positions. The selectivity of the 5 and 22 positions has been found to be very similar, thus reactions under the foregoing conditions will produce a mixture of compounds with sugar 13-Hydroxy milbemycin ag and ctg have hydroxy -12- 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 • 1 868 5 1 1 rni I tt in moieties at the 5, the 22 and at both positions. Chromatographic techniques have been found to be very-useful in separating mixtures of these compounds. In this manner, any combination of compounds with more than one available hydroxy group may be selectively substituted with the above sugar moieties. The following examples are provided in order that the reaction might be more fully understood. They should not be construed as limitative of the invention. EXAMPLE 1 13-(2,3,4,6,-Tetra-O-acetyl-O-glucopyranosyloxy) milbemycin g0 To a solution of 13-hydroxy milbemycin (280 mg.)in anhydrous ether (precautions are taken to insure anhydrous conditions of solvent and glassware) is added freshly prepared silver oxide (230 mg.) and then acetobromoglucose (410 mg.). The mixture is magnetically stirred at ambient temperature for 4 days in the dark. The solids are filtered and washed with ether and the volume of the filtrate is reduced in vacuo. The resulting solution is purified by column chromatography on silca gel using dichloromethane-methanol mixtures as eluant, affording 13-(2,3,4,6-tetra-O-acetyl-O-gluco-pyranosyloxy) milbemycin a2* -13- 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 • 1 8685 f 10012 EXAMPLE 2 13-(D-glucopyranosyloxy) milbemycin The acetylated glucopyranosyl derivative (50 mg.) of Example 1 is treated with sufficient methanolic ammonia (2 ml., presaturated at 0°) to cover the starting material, and the reaction is monitored by thin layer chromatography at one hour intervals. The reaction is complete in 6 hours and the solvent is removed in vacuo. The product purified by column chromatography using a dichloromethane-methanol mixture as eluant. EXAMPLE 3 5-0- (2,3,4, 6-Tetra-0-acetyl-(3-0-glucopyranosyl) milbemycin a-^ To a mixture of milbemycin (560 mg.), acetobromoglucose (820 mg.) and diisopropylethylamine (260 mg.) in anhydrous ether (precautions are taken to insure anhydrous conditions of solvent and glassware) is added silver triflate (280 mg.). The mixture is stirred (magnetically) at ambient temperature in the dark until further reaction stops (as monitored by thin layer chromatography). 24 Hours reaction time is required. The solids are filtered, washed with ether and the filtrate is partitioned with aqueous dilute sodium bicarbonate, separated, washed with water, and dried over sodium sulfate. The solvent is removed in vacuo and the product is purified by column chromatography on silca gel using dichloromethane-methanol mixtures as eluant. -14- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 • 1 8685 1 3H5012 IA. EXAMPLE 4 5-0-, (3-D-Glucopyranosyl) milbemycin Following the procedure of Example 2, the peracetylated glucopyranosyl milbemycin of Example 3 is treated with methanolic ammonia and the product 5-0-(3-D-glucopyranosyl) milbemycin isolated. (250 mg.) in vigorously anhydrous dichloroethane is added 3,4-di-O-acetyl-l,2-methylorthoacetyl-3-L-rhainnopyranose (450 mg.) and mercuric bromide (360 mg.) The mixture is heated at reflux under nitrogen with slow removal of solvent (and formed methanol) by distillation. Solvent removed by distillation is replaced with fresh solvent from a dropping funnel. The reaction is monitored by thin layer chromatography and when it ceases to make further progress is cooled, washed with 30% aqueous potassium iodide, water and dried over sodium sulfate. Column chromatography using chloroform-methanol mixtures as eluants resolves the glycosidic products. After lyophilization from benzene the product 13-(2,3,4-tri-O-a-L-rhamnopyranosyloxy) milbemycin a ig isolate<3 as an amorphous solid. EXAMPLE 6 13-(a-L-rhamnopyranosyloxy) milbemycin Following the procedure of Example 2 using the product of Example 5 as starting material, there is obtained 13-(a-L-rhamnopyranosyloxy) milbemycin a^. -15- EXAMPLE 5 13-(2,3,4-tri-O-acetyl-a-L-rhamnopyranosyloxy) milbemycin a 1 To a solution of 13-hydroxy milbemycin 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 8685 1 i££-±£-£fc- EXAMPLE 7 13-(L-oleandrosyl-g-L-oleandrosyl)-milbemycin g^ The procedure of Example 1 is followed employing 100 mg. of 5-0-acetyl-13-hydroxy milbemycin g^ in place of 13-hydroxy milbemycin a2 and 250 mg. of 4-O-acetyl-a-L-oleandrosyl-L-oleandrosyl-L-oleandrosyl chloride in place of acetobromoglucose. (The halogenose is also known as 4-0(4-0-acetyl-2,6-dideoxy-3-0-methyl-a-L-lyxo-hexopyranosyl)-2,6-dideoxy-3-0-methyl-L- lyxo-hexopyranosyl chloride). The product is purified using preparative layer chromatography affording 13-(4-0-acetyl-a-L-oleandrosyl-L-oleandrosyl)-5-O-acetyl-milbemycin . The above compound is hydrolyzed according to the procedures of Example 2, affording 13-(L-oleandrosyl-a-L-oleandrosyl) milbemycin a^. EXAMPLE 8 5-0-Acetyl-22-(4-O-Acetyl-a-L-Oleandrosyl-a-L-oleandrosyl-oxy) Milbemycin Cg A solution of 100 mg. of milbemycin a.g is treated with 250 mg. of 4-O-acetyl-g-L-oleandrosyl-L-oleandrosyl chloride (also named as 4-0-(4-0-acetyl-2,6-dideoxy-3-0-methyl-a-L- lyxo hexopyranosyl)-2,6-dideoxy-3-O-methyl-L- lyxo hexopyranosyl chloride) following the procedure of Example 3. The product 22-(4-0-acetyl-c-L-oleandrosyl-a-L-oleandrosyloxy) milbemycin gg is isolated and purified on preparative layer chromatography plates using methylene chloride methanol mixtures as solvent. -16- 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 # 1860 5 1 W 1G012 XA- EXAMPLE 9 22- (4-0-Acetyl-g-I.-01eandrosyl-a-L-oleandrosyloxy) Milbemycin ctg The product of Example 8 is hydrolized following the procedure of Example 2 to produce 22-(a-L-oleandrosyl-a-L-oleandrosyloxy) milbemycin PREPARATIONS A. 13-Bromo milbemycin a2 A solution of 542 mg. of milbemycin 178 mg. of N-bromosuccinimide in 10 ml. of carbon tetrachloride is stirred under irradiation with ultraviolet light for 1 hour at room temperature. The mixture is cooled to 0°C, the succinimide is filtered off and the solvent is removed by evaporation under reduced pressure. Chromatography of a solution of the residue in a mixture of chloroform and tetrahydrofuran (95:5) over a column of silica yields 13-bromo milbemycin a2 • B. 13-Acetoxy milbemycin a2 A solution of 621 mg. of 13-bromo milbemycin a2 and 82 mg. of anhydrous sodium acetate in 10 ml. of acetic acid is stirred for 24 hours at 20°C-30°C. The acetic acid is evaporated under reduced pressure and the product is separated from the sodium bromide by extraction with ether and evaporation. Chromatography of the product extracted into the ether in a mixture of chloroform and tetrahydrofuran (95:5) over a column of silica yields 13-acetoxy milbemycin a2- -17- • 1 8685 f 2^012 Ift 1 C. 13-Hydroxy milbemycin a2 2 A solution of 600 mg. of 13-acetoxy 3 milbemycin a2 and 44 mg. of sodium hydroxide in a 4 mixture of 8 ml. of methanol and 2 ml. of water is 5 stirred for 10 hours at 0°-10°C. The solvent is 6 evaporated under reduced pressure and the residue is 7 dissolved in chloroform. Chromatography of the 8 chloroform solution over a column of silica yields 13- 9 hydroxy milbemycin a2• 10 D. Other milbemycin compounds such as a^, a^, a^, 11 a.g, a^, ag,' a<j, 0^, (32 and ^ may be similarly 12 converted into the 13-hydroxy derivatives either before or 13 after the sugar reactions described above. 14 The novel compounds of this invention have 15 significant parasiticidal activity as anthelmintics, 16 insecticides and acaricides, in human and animal 17 health and in agriculture. 18 The disease or group of diseases described 19 generally as helminthiasis is due to infection of an 20 animal host with parasitic worms known as helminths. 21 Helminthiasis is a prevalent and serious economic 22 problem in domesticated animals such as swine, sheep, 23 horses, cattle, goats, dogs, cats and poultry. Among 24 the helminths, the group of worms described as nematodes 25 causes widespread and often times serious infection in 26 various species of animals. The most common genera of 27 nematodes infecting the animals referred to above are 28 Haemonchus, Trichostrongylus, Ostertagia, Nematodirus , 29 Cooperia, Ascaris, Bunostomum, Oesophagostomum, Chabertia, 30 Trichuris, Strongylus, Trichonema, Dictyocaulus, -18- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1 8685 1 16011! Ifr Capillaria, Heterakis, Toxocara, Ascaridia, Oxyuris, Ancylostoma, Uncinaria, Toxascaris and Parascaris. Certain of these, such as Nematodirus, Cooperia, and Oesophagostomum attack primarily the intestinal tract while others, such as Haemonchus and Ostertagia, are more prevalent in the stomach, while still others such as Dictyocaulus are found in the lungs. Still other parasites may be located in other tissues and organs of the body such as the heart and blood vessels, subcutaneous and lymphatic tissue and the like. The parasitic infections known as helminthiases lead to anemia, malnutrition, weakness, weight loss, severe damage to the walls of the intestinal tract and other tissues and organs and, if left untreated, may result in death of the infected host. The milbemycin derivatives of this invention have unexpectedly high activity against these parasites, and in addition are also active against Dirofilaria in dogs, Nematospiroides, Syphacia, Aspiculuris in rodents, arthropod ectoparasites of animals and birds such as ticks, mites, lice, fleas, blowfly, in sheep Lucilia sp., biting insects and such migrating dipterous larvae as Hypoderma sp. in cattle, Gastrophilus in horses, and Cuterebra sp. in rodents. The instant compounds are also useful against parasites which infect humans. The most common genera of parasites of the gastro-intestinal tract of man are Ancylostoma, Necator, Ascaris, Strongyloides, Trichinella, Capillaria, Trichuris, and Enterobius. Other medically important genera of parasites which are found in the blood or other tissues and organs outside -19- • 18MJ 1 the gastro-intestinal tract are the filiarial worms 2 such as Wuchereria, Brugia, Onchocerca and Loa, 3 Dracunculus and extra intestinal stages of the intestinal 4 worms Strongyloides and Trichinella. The compounds are 5 also of value against arthropods parasitizing man, g biting insects and other dipterous pests causing 7 annoyance to man. g The compounds are also active against 9 household pests such as the cockroach, Blatella sp., 10 clothes moth, Tineola sp., carpet beetle, Attagenus sp. 11 and the housefly Musca domestica. 12 The compounds are also useful against insect 13 pests of stored grains such as Tribolium sp., Tenebrio 14 sp. and of agricultural plants such as spider mites, 15 (Tetranychus sp.), aphids, (Acyrthiosiphon sp.); 15 against migratory orthopterans such as locusts and 17 immature stages of insects living on plant tissue. ig The compounds are useful as a nematocide for the control 19 of soil nematodes and plant parasites such as Meloidogyne 20 spp. which may be of importance in agriculture. 21 These compounds may be administered orally in 22 a unit dosage form such as a capsule, bolus or tablet, 23 or as a liquid drench where used as an anthelmintic 24 in mammals. The drench is normally a solution, suspension 25 or dispersion of the active ingredient usually in water 26 together with a suspending agent such as bentonite and 27 a wetting agent or like excipient. Generally, the 28 drenches also contain an antifoaming agent. Drench 29 formulations generally contains from about 0.001 to 30 0.5% by weight of the active compound. Preferred drench -20- • 1 8685 1 i6&±V-±A ]_ formulations may contain from 0.01 to 0.1% by weight. 2 The capsules and boluses comprise the active ingredient 3 admixed with a carrier vehicle such as starch, talc, 4 magnesium stearate, or di-calcium phosphate. 6 derivatives in a dry, solid unit dosage form, capsules, 7 boluses or tablets containing the desired amount of g active compound usually are employed. These dosage 9 forms are prepared by intimately and uniformly mixing 10 the active ingredient with suitable finely divided 11 diluents, fillers, disintegrating agents and/or 12 binders such as starch, lactose, talc, magnesium stearate, 13 vegetable gums and the like. Such unit dosage 14 formulations may be varied widely with respect to their 15 total weight and content of the antiparasitic agent 16 depending upon factors such as the type of host animal 17 to be treated, the severity and type of infection and 18 the weight of the host. 19 When the active compound is to be administered 20 via an animal feedstuff, it is intimately dispersed in 21 the feed or used as a top dressing or in the form of 22 pellets which may then be added to the finished feed 23 or optionally fed separately. Alternatively, the 24 antiparasitic compounds of our invention may be 25 administered to animals parenterally, for example, by 26 intraruminal, intramuscular, intratracheal, or subcutaneous 27 injection in which event the active ingredient is 28 dissolved or dispersed in a liquid carrier vehicle. For 29 parenteral administration, the active material is 30 suitably admixed with an acceptable vehicle, preferably 5 Where it is desired to administer the milbemycin -21- </div>

Claims

<div class="application article clearfix printTableText" id="claims"> • 1 8685 1 of the vegetable oil variety such as peanut oil, cotton 2 seed oil and the like. Other parenteral vehicles such 3 as organic preparation using solketal, glycerol, formal 4 and aqueous parenteral formulations are also used. The 5 active milbemycin compound or compounds are dissolved or 6 suspended in the parenteral formulation for 7 administration; such formulations generally contain from g 0.005 to 5% by weight of the active compound. -22- r 0. .< Q R t v w O ^ » WHAT WE CLAIM IS:

1. A compound having the formula: wherein.R is hydrogen or a sugar (glycosyloxy) moiety and R^, R2, R^, R^ and R' are defined as follows: JJ H fl ch3 *;ch, 3;h;*1 or sugar H h - ch3 ce3 ce3 h e e e C2H5 ' C2H5 ch3 ch3 e or sugar ^3 -oe or sugar fl <th3 -o-c-ce-c4h9 ch3 ch3 h or sugar -oh or sugar 0 ch, 11 1 -0-c-ch-c4eg ch3 ch3 ch3 -oe or sugar 0 ch II 1 3 -oc-ch-c4hg C2H5 ch3 e or sugar -oe or sugar 0 ch ii 1 -oc-ch-c4h9 C2H5 ch- cn3 H H ch3 -cs2o^-g) h or sugar e K C2H5 -ch2o!!jg] K or sugar or 186851 R"H20 wherein R is hydrogen or a sugar (glycosyloxy) moiety and " R2, R' and R" are defined as follows: ch- C2H5 CH, 51 ch3 ch3 H or sugar R" -OH or -O-sugar -OH or -O-sugar H provided that in the first of the above structural formulae at least one of R, R^ and R' is a sugar moiety and in the second of the above structural formulae at least one of R, R', and R" is or contains a sugar moiety.

2. A compound of the first structural formula in claim 1 wherein R is hydrogen or a sugar (glycosyloxy) moiety, R^ and R2 are hydrogen and R3, R^ and R' are defined as follows: h. ch, ch. C2H5 C2H5 CH. CH3 CH3 ch3 CH, 3 0 II -CH2OC R' H or sugar ch3 H or sugar ch3 H or sugar or a compound of the second structural formula in claim 1 wherein R is hydrogen or a sugar (glycosyloxy) moiety, R2 and R' are CH3 and R11 is -OH or -O-sugar, provided that at least one of R and R1 or R and R' ' is or contains a sugar moiety. 24 - 18685!

3. A compound of Claim 1 or Claim 2 wherein the sugar moiety is a mono-, di- or trisaccharide selected from glucopyranosyl, galactopyranosyl, mannopyranosyl, maltosyl, arabinopyranosyl, lyxopyranosyl, xylopyranosyl, ribopyranosyl, oleandrosyl, rhamnopyranosyl, fucopyranosyl, lactosyl, ribofuranosyl, mannofuranosyl, glucofuranosyl, arabinofuranosyl, mycarosyl, cladinosyl, desosaminosyl, daunosaminosyl, and mycaminosyl.

4. A compound of Claim 3 wherein the sugar moiety is a mono or disaccharide selected from glucopyranosyl, rhamnopyranosyl, oleandrosyl and daunosaminosyl.

5. A compound of Claim 4 wherein the sugar moiety is a mono or disaccharide selected from glucopyranosyl and oleandrosyl.

6. The compound of Claim 5 which is 13-($-D-glucopyranosyloxy) milbemycin a^.

1. The compound of Claim 5 which is 5-0-(S-D-glucopyranosyl) milbemycin a^.

8. A compound of Claim 5 wherein the sugar rroiety is L-oleandrosyl-a-L-oleandrosyl.

9. The compound of Claim 8 which is 13-(L-oleandrosyl-a-L-oleandrosyl) milbemycin a^.

10. The compound of claim 8 which is 5-0-(L-oleandrosyl-a-L-oleandrosyl) milbemycin ci^. ■_ - 25 - !86851

11. The compound of Claim 8 which is 13-(L-oleandrosyl-ct-L-oleandrosyl) milbemycin

12. A process for the preparation of a compound of Claim 1 or Claim 2 which comprises treating a milbemycin compound or a 13-hydroxy milbemycin compound with an aceto-halo-sugar in the presence of silver oxide, and removing the acetyl protecting groups by hydrolysis.

13. A process of Claim 12 wherein a mercuric halide alone or in combination with mercuric oxide or mercuric cyanide is employed in place of silver oxide.

14. A process for the preparation of a compound of Claim 1 or Claim 2, which comprises treating a milbemycin compound or a 13-hydroxy milbemycin compound with an aceto-halo-sugar in the presence of silver trifluoromethylsulfonate and a non-nucleophilic base.

15. A process for the preparation of a compound of Claim 1 or Claim 2 which comprises treating a milbemycin compound or a 13-hydroxy milbemycin compound with an ortho ester of a sugar in the presence of catalytic amounts of mercuric bromide or mercuric chloride.

16. A method for the treatment of parasitic infections, which comprises administering to a non-human animal infected with parasites, an effective amount of a compound of Claim 1 or Claim 2. DATED THIS iovL ftp-f OF A . , ? A 3 K ft S 0 N Jf r 5. 26 - </div>