NZ201702A - 1 alpha,25-dihydroxy-(24r or 24s)-fluorocholecal-ciferol and intermediates;pharmaceutical compositions - Google Patents

Abstract

1. Claims for the contracting states : BE, CH, DE, FR, GB, IT, LI, LU, NL, SE A cholecalciferol derivative of the formula see diagramm : EP0073465,P14,F3 1. Claims for the contracting state : AT A process for the manufacture of a cholecalciferol derivative of the formula see diagramm : EP0073465,P16,F1 characterized by thermally isomerizing a precholecalciferol derivative of the formula see diagramm : EP0073465,P16,F3

Description

New Zealand Paient Spedficaiion for Paient Number £01 70£ 201702 NO Priority Date(s): OZT-S'S^-Complete Specification Filed: -r.........

Class: .

Publication Date: P.O. Journal, No: ..fisMjwf /273:><ii /■ V t 5 APK . - J> *r. V •." 2 3 "NUV -X NEW ZEALAND PATENTS ACT, 1953 No.

Date COMPLETE SPECIFICATION CHOLECALCIFEROL DERIVATIVES, THEIR MANUFACTURE, AND INTERMEDIATES We, F. HOFFMANN-LA ROCHE & CO. AKTIENGESELLSCHAFT, 124-184 Grenzacherstrasse, Basle, Switzerland, a Swiss company, hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : - (followed by page la) 20170: -la- RAIJ 4212/31 The present invention is concerned with novel chole- calciferol derivatives of formula ho' The invention is also concerned with pharmaceutical 25 preparations on the basis of the compounds of formula I, process for the manufacture of these compounds and intermediates occuring in said process.

The compounds of formula I are manufactured in 30 accordance with the invention by thermally isomerising a precholecalciferol derivative of formula Me/ 3Q. 7.02 201702 f ho rw IIA h ho In the formulae presented herein a wavy line between a C atom and a substituent indicates that the absolute configuration at the C atom is R or S, or that the corres-15 ponding compound is in form of a R,S-mixture.

The thermal isomerization of a compound of formula II-A can be carried out by heating in an inert solvent, such as an ether, e.g. dioxane, tetrahydrofuran or dimethoxyethane; 20 an aromatic hydrocarbon, e.g. benzene or toluene, under an inert atmosphere, such as argon or helium, by methods well known in the art, see e.g. J.A.C.S. 98 (1973) 2748. containing 1 to 8 carbon atoms. Examples of lower alkyl groups are methyl, ethyl, n-propyl, i-propyl, tert.-butyl, hexyl, heptvl and octyl. Examples of lower alkylene groups are methylene, ethylene and propylene. Examples of lower alkoxy groups are methoxy, ethoxy, isopropoxy and tert.-30 butoxy. Examples of lower alkanoyloxy groups are formyloxy, acetoxy, butyryloxy and hexanoyloxy. The term "substituted" as applied to "phenyl" refers to phenyl which is substituted with one or more groups; such as lower alkyl, fluoro, chloro, bromo, iodo, nitro, cyano or trifluoromethyl.

As used hereinafter, the term "lower" refers to groups The compounds of formula II-A can be manufactured by reacting a compound of formula 201702 -ch3 ii, w ch3 wherein X is iodo, bromo, chloro, lower alkylsulfonyl-oxy, phenylsulfonyloxy or substituted phenylsulfonyl-oxy, and Y is a group of the formula R - 0 - R1 I C -R2 wherein R is hydrogen or lower alkyl, and R and 3 2 3 R are each lower alkyl or R and R taken together are C3_g-alkylene, with a metallated pregn-5-en-21-oic acid ester of formula IVA wherein M is lithium, sodium, potassium, magnesium/2 4 or zinc/2, R is lower alkyl, phenyl or substituted 30 phenyl and Y is as above, according to the method described in J.Chem.Soc., Perkin Trans. I, 1282 (1978), to give the corresponding alkylated compound of formula * 28FEBI985 m 201702 r4o2c.„ VA 4 wherein R and Y are as above.

This reaction may be carried out in an aprotic inert solvent, such as an ether, e.g. tetrahydrofuran; or an 15 amide, e.g. hexamethylphosphoramide, conveniently at a temperature between -78 and 60°C. The product of formula V-A, containing the desired 20R-absolute configuration, can be isolated by the usual chemical and physical means.

The compound of formula V-A is then reduced to the alcohol of formula VB wherein Y is as above, by reaction with a complex metal hydride reducing agent, such as an alkali metal aluminum hydride, e.g. lithium aluminum hydride; a mono-, di- or tri-(lower alkoxy) alkali metal aluminum hydrides, e.g. lithium tris(tert.-butoxy)- 20170 aluminum hydride; a mono-, di- or tri(lower alkoxy-lower alkoxy) alkali metal aluminum hydrides, e.g. sodium bis(2-methoxyethoxy)aluminum hydride; or a di(lower alkyl) aluminum hydrides, e.g. diisobutyl aluminum hydride. Sui-5 table solvents for this reduction include ethers, such as diethyl ether. The reduction is conveniently carried out at a temperature between about 0°C and 100°C.

The alcohol of formula V-B is then converted in a 10 manner known per se to the halide or sulfonate of formula xh2c,. vc wherein X and Y are as above.

To prepare a sulfonate of formula V-C, the compound of formula V-B is reacted with a sulfonyl halide in the presence of a base. The preparation of a halide of formula V-C can be accomplished either by reacting the alcohol of formula V-B with a halogenating agent, such as phosphorus tribromide, or by reaction of a sulfonate ester of formula V-C e.g. a tosylate, with a halide ion containing compound, such as an alkali metal bromide or iodide, e.g. potassium bromide.

The compound of formula V-C is then converted to the compound of formula )702 6 f YO VD ch3 i h h h yo wherein Y is as above, with a complex metal hydride reducing agent.

The reduction is normally carried out with one of the 15 reducing agents and in one of the solvents mentioned above in connection with the reduction of a compound V-A to a compound V-B, at a temperature between about room temperature and 100°C. Other suitable reducing agents, particularly when X is iodo or bromo, are alkali metal cyanoborohydrides 20 such as, sodium cyanoborohydride (sodium cyanotrihydro-borate); tri (lower alkyl) tin hydrides, such as tri-n-butyltin hydride; and tri (aryl) tin hydrides, such as triphenyltin hydride. The reduction is normally carried out at a temperature between about -20 and 80°C.

The compound of formula V-D is then converted to the la,25-dihydroxy-24-fluorocholesterol of formula f VE 201702 by removal of the protecting groups Y with a strong acid in a protic solvent. Suitable strong acids include mineral acids, such as hydrochloric acid, and organic sulfonic acids, such as p-toluenesulfonic acid. Suitable solvents include alcohols, such as methanol, and water containing a miscible co-solvent to help solubilize the organic reactants, such as ethers, e.g. tetrahydrofuran; or a ketone, such as acetone. The reaction is preferably carried out at a temperature between about -10 and 80°C.

The cholesterol of formula V-E is then alkanoylated to the la,33-dialkanoate of formula r5o VIA wherein R is lower alkanoyl, 25 by methods well known in the art.

The compound of formula VI-A is allylically halogenated to a mixture of 7a- and 73-halocholesterols of formula f VIB 201702 wherein R is as above and Z is iodo, bromo or chloro, using a halogenation agent, such as N-chloro- or N-brorno-succinimide, dissolved in a saturated aliphatic hydrocarbon or halocarbon, such as hexane, in the presence of an acid 5 scavenger, such as sodium bicarbonate, at the boiling point of the reaction medium.

Without separation of the 7(3-halo-isomer from the predominant 7a-isomer, the compound of formula VI-B is dehydro-10 halogenated to the steroid-5,7-diene of formula VIC wherein R is as above, utilizing a heteroaromatic tertiary amine, such as a pyridine, e.g. picolines, lutidines and collidines; or an ali-25 phatic tertiary amine, e.g. triethylamine, tripropylamine, 1,5-diazabicyclo(4.3.0) non-5-ene or 1 , 4-diazabicyclo(2.2.2) octane. Trialkylphosphites are also useful in the dehydro-halogenation step. Suitable inert organic solvents include aromatic and aliphatic solvents, such as xylene. The reac-30 tion proceeds readily at temperatures from about 50°C to the reflux temperature of the reaction medium. The steroid 5,7-diene of formula VI-C can be isolated by the usual chemical and physical means, such as chromatography, and in this manner can be separated from any undesired impurities, such 35 as the corresponding 4,6-diene. 201702 The steroid 5,7-diene of formula VI-C is converted to the precholecalciferol-la,33-dialkanoate of formula MB wherein R is as above, by irradiation under an inert atmosphere, such as nitrogen, at a temperature of about -40 to +25°C. Suitable sources of irradiation include high and low pressure mercury lamps. Suitable inert organic solvents for the irradiation include mixtures of saturated aliphatic hydrocarbons and ethereal 20 solvents, such as mixtures of hexane and tetrahydrofuran.

Upon completion of the irradiation, the solvents are removed by evaporation and the residue is separated into the pure precholecalciferol la,33-dialkanoate of formula 25 II-B and pure unchanged steroid 5,7-diene of formula VI-C by liquid chromatography using a solid absorbent, e.g. Porasil, and an inert organic eluant. Suitable eluants include mixtures of hydrocarbons and esters, such as a mixture of n-hexane and ethyl acetate.

Unchanged 5,7-diene of formula VI-C is recycled through the irradiation process to obtain additional quantities of pure precholecalciferol la,33-dialkanoate of formula II-B.

The compound of formula II-B is then saponified to the compound of formula ii-a with a strong base in a protic solvent. Suitable bases include alkali and alkaline earth hydroxides ^ $ r;^ or alkoxides, such as potassium hydroxide. Suitable solvents include alcohols, such as methanol, and water containing a miscible co-solvent to help solubilize the organic reactants, such as an ether, e.g. tetrahydrofuran.

It is preferable to carry out the removal of the alkanoyl 5 groups R at a temperature between about -20 and 60°C and under an inert atmosphere, e.g. nitrogen.

The compounds of formula III can be prepared as shown in the scheme below, wherein R5 and Y have the meaning given above, and as described in the Examples. 201702 The metallated compounds of formula IV-A can be prepared by treating a compound of formula IV B wherein R and Y are as above, with an appropriate organometallic reagent, for example lithium diisopropylamide or sodium hexamethyldisilazane, or with potassium hydride.

The compounds of formula IV-B can be prepared as shown 4 in the sheme below, wherein Y and R are as above, and as described in the Examples ivc iv d COoR |V-B The compounds of formulae II-A and II-B, i.e. of formula ' .

I c *;v 28FEBI985' is «^ V oi 201702 II wherein is hydrogen or lower alkanoyl, are novel and also form part of the present invention. The compounds of formulae VI-A, VI-B and VI-C, i.e. of formula FPO VI wherein Q is hydrogen and Z' is hydrogen, iodo, bromo or chloro, or Q and Z'taken together are an additional 7,8-bond and R^ is as above, those of formulae V-A, V-B, V-C, V-D and V-E, i.e. of formula 201702 13 wherein Y' is hydrogen or a group Y and X' is methyl, or Y' is a group Y and X' is -CH_X, -CH OH or -COOR4, 4 and Y, X and R are as above, those'of formula IV-A and IV-B, i.e. of formula are as above, as well as those of formulae 2, 3, III-A, III-B, III-C and III are novel. The compounds of formulae VI and V are described and claimed in our New Zealand Patent Specification No. 210 826 and the compounds of formula IV are described and claimed in our New Zealand Patent Specification No. 210827.

The compounds of formula I are characterized by the ability to increase intestinal calcium transport, to increase serum calcium and phosphate concentrations and to increase the deposition of these minerals in bones. These compounds will find application as substitutes for la,25-dihydroxycholecalciferol in the treatment of disease states characterized by metabolic calcium and phosphate deficiencies, such as osteomalacia, osteoporosis, rickets, osteitis fibrosa cystica, renal osteodystrophy, osteosclerosis, convulsions, osteopenia, fibrogenesis imperfecta ossium, secondary hyperparathyroidism, hypoparathyroidism, hyperparathyroidism, cirrhosis, obstructive jaundice, drug induced metabolism, medullary carcinoma, chronic renal disease, hypophosphatemic vitamin D-resistant rickets, ( vitamin D-dependent rickets, sarcoidosis, glucocorticoid antagonism, malabsorption syndrome, steatorrhea, tropical sprue, idiopatic hypercalcemia and milk fever. yo IV 4 wherein M' is hydrogen or a group M, and M, R and Y 20170 la,25-Dihydroxy-24R-fluorocholecalciferol has shown activity in the anti-rachitogenic test in chicks and has also shown a duration of activity in stimulation of intestinal calcium absorption of 24 hours after a single 5 oral 100 nanogram dose, comparable to that of la,25-dihydroxycholecalciferol .

White Leghorn chicks are placed on a vitamin D-defi-cient diet which contains 1% calcium and 0.7% phosphorous 10 and are housed under ultraviolet-free lighting. The test compounds are dissolved in propylene glycol and administered orally for 21 consecutive days to chicks which are one to two days of age at the start of treatment. Controls are treated with vehicle alone. Chicks are autopsied on the 15 day after the last treatment day and tibia ash weight was determined. Nine or ten chicks are used for each treatment group and for the control group. The results of the la,25-dihydroxy-24R-fluorocholecalciferol (compound X) anti-rachitogenic activity assay are shown in Table I along 20 with comparative data showing the anti-rachitogenic activity of 24,24-difluoro-la,25-dihydroxycholecalciferol (compound A). The results show that la,2 5-dihydroxy-24R-fluorocholecalciferol possesses potent anti-rachitogenic activity.

In an other experiment the chicks are placed on a vitamin D-deficient diet and housed under ultraviolet-free lighting for 21 days. In order to determine the effects of compound X on intestinal calcium absorption, a single oral dose dissolved in propylene glycol is administered. 45 At various times after dosing, 2 y.Ci of Ca (chloride) is given orally and serum radioactivity is measured 45 minutes after administration of the isotope. Vehicle-treated controls are included at each time period. Ten chicks are 35 used in each treatment and control group. The results given in Table II, show that la,25-dihydroxy-24R-fluorocholecalcif erol has intestinal calcium absorption activity of about 24 hours duration.

Dose ng/chick/day 0 3 10 30 201702 Table I Mean tibia ash weight (mg) Compound A X 120.9+8.3 192.2+ 6.2 293.3+ 4.8 258.6+10.0 330.4+ 7.7 229.8+14.2 337.9+10.6 Table II Treatment Time (hours) 45^ Serum Ca cpm/0.2 ml 0.2 ml vehicle 24 compound X 0.2 ml vehicle 48 compound X 0.2 ml vehicle 72 compound X 408+30 793+73 * 439+30 520+38 NS 398+31 372+39 NS * = statistically significant result NS = not statistically significant la,25-Dihydroxy-24R-fluorocholecalciferol can be . administered in dosages that are in the range of about 0.10-3.0, preferably 0.25-2.0 micrograms per day for the treatment of such disease states as osteodystrophy, steroid induced osteopenia, hypoparathyroidism, hypophosphatemic 30 rickets and hypophosphatemic osteomalacia, which are characterized by lower than normal levels of endogenously produced la,25-dihydroxvcholecalciferol. la,25-Dihydroxy-24R-fluorocholecalciferol can be administered orally, subcutaneously, intramuscularly, intravenously, intra-35 peritoneally or topically and can be formulated into compositions, such as tablets, capsules or elixirs for oral administration, or in sterile solutions or suspensions for parenteral administration for the treatment of the afore- 20170 mentioned disease states. The amount of active substance in the foregoing compositions is in the range previously indicated. Illustrative of the adjuvants which may be incorporated into the above compositions are the following: 5 a binder such as gum tragacanth, acacia, corn starch or gelatin; an excipient such as calcium phosphate; a disintegrating agent such as corn or potato starch or alginic acid; a lubricant such as magnesium stearate:, a sweetening agent such as sucrose, lactose or saccharin; a flavoring 10 agent such as peppermint, oil of wintergreen or cherry. Various other materials may be present as coating or to otherwise modify the physical form of the dosage unit. For instance, tablets may be coated with shellac, sugar or both. A syrup or elixir may contain the active compound, 15 sucrose as a sweetening agent, methyl and propyl parabens as preservatives, a dye and a flavoring such as cherry or orange flavor. la,25-Dihydroxy-24R-fluorocholecalciferol can be 20 administered for the treatment of milk fever in pregnant ruminant animals prior to parturation in dosages in the range of 100-1500 micrograms/day using conventional formulations.

Sterile compositions for injection and/or topical administration can be formulated according to conventional practice by dissolving or suspending la,25-dihydroxy-24R-fluorocholecalciferol in a vehicle such as a 10-20% ethanol-water mixture, a 10-20% propylene glycol-water 30 mixture, a naturally-occurring vegetable oil, such as sesame oil, peanut oil, cottonseed oil or a synthetic fatty vehicle, such as ethyl oleate. For example, a suitable formulation for intravenous injection would be 2-3 ml of a 10-20% ethanol-water solution or a 10-20% propylene 35 glycol-water mixture containing 200-1000 micrograms of la,25-dihydroxy-24R-fluorocholecalciferol. Exemplary of a suitable formulation for topical administration would be a vegetable oil solution or suspension containing 200-1000 20170 micrograms of la,25-dihydroxy-24R-fluorocholecalciferol. la,25-Dihydroxy-24R-fluorocholecalciferol can also be formulated for oral administration by incorporation of 5 100-1500 micrograms thereof into fatty acid pellets. la,25-Dihydroxy-24R-fluorocholecalciferol may also be formulated for intramuscular injection by suspension of 100-1500 micrograms of la,25-dihydroxy-24R-fluoro-"10 cholecalciferol in a vehicle such as a vegetable oil, an ethanol-water solution or a propylene glycol-water solution, containing from 80-95% ethanol or propylene glycol. 2017 Example 1 A. A mixture of 0.104 g (0. 00024 mole) of [ la, 3(3 , 6Z , 24R]-24-fluoro-9,10-secocholesta-5(10),6,8-trien-l,3,25-triol and 18 ml of p-dioxane was heated at reflux (100°C) for 1 hr and then cooled. The mixture was evaporated to dryness. The residue was purified by column chromatography on silica gel with 3:1 ethyl acetate-hexane as eluant to give [la,33,5Z,7E,24R]-2 4-fluoro-9,10-secocholesta-5 , 7 , -10 10(19)-trien-1,3,25-triol (la,25-dihydroxy-24R-fluorocholecalcif erol ) , [a]2"^ +68° (c = 0.5, MeOH) .

B. The starting secocholestane can be prepared as follows a) To a solution of 1.2 ml of diisopropylamine in 4 ml of tetrahydrofuran at -30°C was added 4.5 ml (0.0072 mole) of 1.6M of butyllithium in hexane. After stirring for 0.5 hr, 3.57 g (0.0065 mole) of [la,33]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-pregn-5-en-21-oic acid ethyl ester in 36 ml 20 of tetrahydrofuran was added dropwise. The mixture was stirred for 1 hr at -30°C and cooled to -70°C. A solution of 3.40 g (0.011 mole) of 4-(1-ethoxyethoxy)-3R-fluoro-1-iodo-4-methylpentane in 6 ml of hexamethylphosphoramide was added dropwise. The mixture was stirred at -70°C for 1 hr 25 and allowed to warm to 25°C and stir for 1 hr. The mixture was diluted with 9:1 hexane-ether. The solution was washed with water and saturated brine. The organic phase was dried filtered and evaporated to dryness. The residue was purified by column chromatography on silica gel to give 30 [la,33,24R]-l,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-( 1- ethoxyethoxy)-24-fluoro-cholest-5-en-21-oic acid ethyl ?n ester, +18° (c = 1, CHCl^)- b) To a mixture of 0.34 g (0.0090 mole) of lithium alu-35 minum hydride and 17 ml of tetrahydrofuran at 0°C was added 4.26 g of [la,33,24R]-1,3-bis[(tetrahydro-2H-pyran-2-yl)-oxy]-25-(l-ethoxyethoxv)-24-fluorocholest-5-en-21-oic acid 201702 ethyl ester in 60 ml of tetrahydrofuran. The mixture was heated at 50°C for 1.5 hr, cooled to 0°C and diluted with 200 ml of ether. The mixture was quenched with 0.68 ml of water and 0.55 ml of 10% aqueous sodium hydroxide. The mixture was stirred at 25°C for 0.5 hr and filtered. The solids were triturated with ether and filtered. Evaporation of solvent afforded [la,33,24R]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-24-fluorocholest-5-en-21-ol, [a]25 + 7° (c = 1.1, CHC13). c) A mixture of 3.99 g (0.0058 mole) of [la,33,24R]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-2 5-(1-ethoxyethoxy)-2 4-fluorocholest—5-en-21-ol, 15 ml of pyridine and 2.20 g (0.0115 mole) of p-toluenesulfonyl chloride was stirred at 15 0°C for 18 hr. The mixture was quenched with ice chips. The mixture was then poured into water and extracted with methylene chloride. The organic phase was washed with 10% aqueous sulfuric acid and saturated sodium bicarbonate solution. The organic layer was dried, filtered and 20 evaporated to dryness to yield [la,33,24R]-1,3-bis[(tetra- hydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-2 4-fluoro- 2 0 cholest-5-en-21-ol 21-( 4-methylbenzenesulfonate ) , fot]D +8° (c = 1, CHC13). d) A mixture of 0.223 g (0. 00026 mole) of [ la, 3[3 , 2 4R]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-2 5-(1-ethoxyethoxy)-24-fluorocholest-5-en-21-ol 21-(4-methylbenzenesulfonate) and 0.150 g (0.0010 mole) of sodium iodide in 2 ml of acetone was heated at 50° for 18 hr and cooled. The mixture 30 was poured into water and the product was isolated with methylene chloride. The organic layers were washed with aqueous sodium sulfite solution and saturated sodium bicarbonate solution. The organic layers were dried, filtered and evaporated to dryness to yield [la,33,24R]-1,3-35 bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-24-fluoro-21-iodocholest-5-ene. 2 017 02 e)l) A mixture of 0.710 g (0.0187 mole) of lithium aluminum hydride, 80 ml of tetrahydrofuran and 4.85 g (0.0057 mole) of [la,33,24R]-l,3-bis[( tetrahydro-2H-pyran-2-yl) oxy]-2 5- (1-ethoxyethoxy)-24-fluorocholest-5-en-21-ol 21-(4-methy1- benzenesulfonate) was heated at reflux (60°C) for 1 hr and cooled to 0°C. The mixture was diluted with 200 ml of ether and quenched with 1.4 ml of water and 1.1 ml of 10% aqueous sodium hydroxide solution. The mixture was stirred for 1 hr and filtered. The solids were triturated with ether and filtered. The combined filtrates were evaporated to dryness and chromatographed on silica gel to yield [la,33,2 4R]-l,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-(l- 2 0 ethoxyethoxy)-24-f luorocholest-5-ene , +7° (c = 1, chci3). e)2) By an alternative procedure, a mixture of 0.206 g (0.00025 mole) of [la,33,24R]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-2 4-fluoro-21-iodocholest-5-ene, 0.087 g (0.00030 mole) of tri-n-butyltin hydride and 3 ml of tetrahydrofuran was stirred at 25°C for 18 hr under an argon atmosphere. The mixture was evaporated to dryness and the residue was purified by chromatography on silica gel to yield [la,33,24R]-1,3-bis-[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-24-fluorocholest-5-ene, 25 [a]21 +7° (c = 1, CHC13). f) A mixture of 3.56 g (0.0053 mole) of [la,33,24R]-1,3-bis-[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-24-fluorocholest-5-ene, 140 ml of methanol and 0.58 g of p-toluenesulfonic acid monohydrate was stirred at 25°C for 3 hr. The mixture was quenched by adding 1.0 g of sodium bicarbonate and stirring for 0.5 hr. The mixture was evaporated to dryness. The residue was triturated with ethyl acetate, filtered and evaporated to dryness. The crude 35 solid was recrystallized from ethyl acetate to yield [la,33,24R]-24-fluorocholest-5-en-l,3,25-triol, mp 156-158°C, [a]^1 +4° (c = 0.5, MeOH). 20170 g) A mixture of 1.53 g ( 0.0035 mole) of [ la, 3(3 , 24R ]-24- fluorocholest-5-en-l,3,25-triol, 13 ml of pyridine and 6 ml of acetic anhydride was stirred at 0°C for 1 hr and at 25°C for 17 hr. The mixture was diluted with 20 ml of 5 methanol at 0°C and evaporated to dryness. The residue was dissolved in methylene chloride. This solution was washed with 10% aqueous sulfuric acid and saturated sodium bicarbonate solution. The organic phase was dried, filtered and evaporated to dryness to yield [la,33,24R]-24-fluoro-"10 cholest-5-en-l,3,25-triol 1 , 3-diacetate , [a]23 -7° (c = 1, chci3). h) A mixture of 0.520 g (0.0010 mole) of [la,33,24R]-24-fluorocholest-5-en-l,3,25-triol 1,3-diacetate, 0.45 g of sodium bicarbonate, 0.192 g (0.00066 mole) of 1,3-dibromo-5,5-dimethylhydantoin and 25 ml of hexane was heated at reflux (80°C) for 1 hr and cooled. The mixture was filtered and the solids were triturated with hexane and filtered. The filtrates were evaporated to dryness to yield [la,33,-20 7^,24R]-7-bromo-24-fluorocholest-5-en-l,3,25-triol 1,3-diacetate. i) A mixture of 0.605 g (0.001 mole) of [la,33,7§,24R]-7-bromo-2 4-fluorocholest-5-en-1,3,25-triol 1,3-diacetate, 0.6 ml of s-collidine and 18 ml of xylene was heated at reflux (140°C) for 0.5 hr and cooled. The mixture was diluted with 30 ml of toluene. This solution was washed with 10% aqueous sulfuric acid and saturated sodium bicarbonate solution. The organic phase was dried, filtered 30 and evaporated to dryness. The residue was purified by column chromatography on silica gel to yield [la,33,24R]-24-fluorocholesta-5,7-dien-l,3,25-triol 1,3-diacetate, [a]23 -21° (c = 0.5, CHCl3). j) A mixture of 0.258 g (0.0005 mole) of [la,33,24R]-24-fluorocholesta-5,7-dien-l,3,25-triol 1 , 3-diacetate in 40 ml of hexane and 10 ml of tetrahydrofuran was irradiated for 0.5 hr under argon at -5°C using a 450W Hanovia high 20170 pressure mercury lamp, cooled with a Vvcor-glass cooling finger. The solution was evaporated to dryness and the residue was purified fcy liquid chromatography on silica gel with a 4:1 mixture of n-hexane-ethyl acetate as eluant( to 5 give [la,33,6Z,24R]-24-fluoro-9,10-secocholesta-5(10),6,8-trien-1,3,25-triol 1,3-diacetate. k) A solution of 0.125 g (0.00024 mole) of [la,33,6Z,24R]-10 24-fluoro-9,10-secocholesta-5(10),6,8-trien-l,3,25-triol 1,3-diacetate and 15 ml of 1% potassium hydroxide in methanol was stirred at 0°C for 4 hr. The mixture was neutralized to pH 7.5 with glacial acetic acid in methanol. The solution was evaporated to dryness at 0°C. The residue 15 was partitioned between ethyl acetate and water. The organic phase was washed with saturated brine and dried. The mixture was filtered and evaporated to dryness to yield [la,33,6Z,2 4R]-24-fluoro-9,10-secocholesta-5(10),6,8-trien-1,3,25-triol.

C. The intermediate, 4-(1-ethoxyethoxy)-3R-fluoro-l-iodo-4-methylpentane, can be prepared as follows: a) To a solution of 16.5 g (0.102 mole) of diethylamino- sulfur trifluoride in 20 ml of methylene chloride at -70°C was added dropwise 3.50 g (0.034 mole) of (-)-2S- hydroxy-4-butyrolactone in 30 ml of methylene chloride.

The mixture was stirred at -70°C for 1 hr and was warmed to 25°C and stirred 1 hr. The mixture was poured into saturated sodium bicarbonate solution at 0°C. The product was extracted with methylene chloride. The organic phase was dried, filtered and evaporated to dryness. The residue was purified by column chromatography on silica 22 gel to yield 2R-fluoro-4-butyrolactone, +50° (c = 1, CHCl 3 ) . do ^ Ei b) To a solution of 16.8 ml of 1.5M ethereal methyl-lithium (0.025 mole) at 0°C was added dropwise 1.05 g (0.010 mole) of 2R-fluoro-4-butyrolactone in 35 ml of ether. The mixture was stirred at 0°C for 1 hr and at 25°C for 1 hr. The mixture was quenched by adding 2 ml of saturated brine at 0°C. The mixture was poured into saturated brine and the product was isolated with ether. The ether layers were dried, filtered and evaporated to dryness to give 22 4-methyl-3R-fluoro-1,4-pentanediol, +39° (c = 1, chci3). c) To a mixture of 0.540 g (0.0040 mole) of 4-methyl-3R-fluoro-1,4-pentanediol and 3 ml of pyridine at 0°C was added 2 ml of acetic anhydride and the mixture was stirred at 0°C for 1 hr and at 25°C for 1 hr. The mixture was added to 10 ml of methanol and the solution was evaporated to dryness to yield 4-methyl-3R-fluoro-1,4-pentanediol 1-acetate, [a]^2 +49° (c = 0.5, CHCl^). d) A mixture of 2.48 g (0.014 mole) of 4-methyl-3-R-fluoro-1,4-pentanediol 1-acetate, 65 ml of ethyl vinyl ether and 0.25 g of p-toluenesulfonic acid monohydrate was stirred at -70°C for 1 hr. The mixture was quenched by adding 8 ml of triethylamine and evaporated to dryness. The residue was taken up in ether. This solution was successively washed with saturated sodium bicarbonate solution and saturated brine. The ether phase was dried, filtered and evaporated to dryness to yield an oil containing 4-(l-ethoxyethoxy)-3R-fluoro-4-methyl-l-pentanol 1-acetate. e) To a mixture of 0.79 g (0.021 mole) of lithium aluminum hydride in 40 ml of ether at 0°C was added dropwise 3.48 g (0.014 mole) of 4-(1-ethoxyethoxy)-3R-fluoro-4-methyl-1-pentanol 1-acetate in 100 ml of ether. The mixture was heated at reflux for 3 hr and then was cooled to 0°C. The mixture was quenched by adding dropwise 1.5 ml of water followed by 1.2 ml of 10% aqueous sodium hydroxide. The mixture was stirred at 25°C for 0.5 hr and was filtered. 201702 The solids were triturated with ether and filtered. Evaporation of solvent and column chromatography of the residue on silica gel afforded 4-(1-ethoxyethoxy)-3R- 24 fluoro-4-methyl-1-pentanol, +18° (c = 1, CHCl^). f) A mixture of 3.34 g (0.016 mole) of 4-(1-ethoxyethoxy) 3R-fluoro-4-methyl-l-pentanol, 12 ml of pyridine and 4.67 g (0.024 mole) of p-toluenesulfonyl chloride was stirred at 0°C for 18 hr. The mixture was quenched with ice chips^then poured into water and extracted with methylene chloride. The organic phase was sequentially washed with 10% aqueous sulfuric acid and saturated sodium bicarbonate solution. The organic phase was dried, filtered and evaporated to dryness to yield oily 4-(1-ethoxyethoxy)-3R-15 fluoro-4-methyl-1-pentanol 1-(4-methylbenzenesulfonate). g) A mixture of 5.42 g (0.015 mole) of 4-(1-ethoxyethoxy) 3R-f luoro-4-rnethyl-l-pentanol l-(4-methylbenzenesulfonate), 70 ml of acetone, 1 ml of diisopropylethylamine and 30.3 g (0.202 mole) of sodium iodide was stirred at 25°C for 18 hr The mixture was evaporated to dryness. The residue was partitioned between 5% aqueous sodium sulfite solution and methylene chloride. The organic phase was washed with saturated sodium bicarbonate solution, then dried, filtered and evaporated to dryness to yield 4-(1-ethoxyethoxy )-3R-fluoro-1-iodo-4-methylpentane, [a]2^ +43° (c = 1, chci3).

D. The intermediate, [ la, 3(3-1 , 3-bis [(tetrahydro-2H-pyran-30 2-yl)oxy]-pregn-5-en-21-oic acid ethyl ester, can be prepared as follows: a) A mixture of 0.91 g (0.0030 mole) of la,33-dihydroxy-androst-5-en-l7-one, 15 ml of tetrahydrofuran, 1.26 g 35 (0.015 mole) of 3,4-dihydro-2H-pyran and 0.028 mg of p-toluenesulfonic acid monohydrate was stirred at 25°C for 18 hr. The mixture was diluted with methylene chloride. 20170 This solution was then washed with saturated sodium bicarbonate solution. The organic phase was dried, filtered and evaporated to dryness to yield [la,33]-1,3-bis-[(tetra- hydro-2H-pyran-2-yl )oxy]androst-3-en-l 7-one , +34.3° (c = 1, CHC13). b) To a mixture of 1.00 g (0.0021 mole) of [la,33]-bis-[(tetrahydro-2H-pyran-2-yl)oxy]androst-3-en-l7-one, 1.94 g (0.0087 mole) of triethyl phosphonoacetate and 14 ml of ethanol was added 0.68 g (0.010 mole) of sodium ethoxide in 7 ml of ethanol. The mixture was stirred at reflux for 18 hr and cooled. The mixture was concentrated under reduced pressure, then partitioned between water and ether and the organic phase was washed with saturated brine The organic phase was dried, filtered and evaporated to dryness. The residue was chromatographed on silica gel to yield [la,33,17(20)E]-l,3-bis[(tetrahydro-2H-pyran-2-yl)- oxy lpregna-5 ,17 (10 )-dien-21-oic acid ethyl ester, -8° (c = 1, CHC13). c) A mixture of 0.32 g (0.00059 mole) of [la,33,17(20E]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]pregna-5,17(20)-dien-21-oic acid ethyl ester, 0.10 g of platinum oxide and 20 ml of ethanol was stirred in 1 atmosphere of hydrogen for 2 hr The mixture was filtered through diatomaceous earth and the solids were washed with ethanol. The combined filtrates were evaporated to dryness to yield [la,33]-1,3-bis[(tetra-hydro-2H-pyran-2-yl)oxy]pregn-5-en-21-oic acid ethyl ester, [a]23 -13° (c = 1, CHC13).

Example 2 A. In a manner similar to that described in Example lA [la,33,6Z,24S]-24-fluoro-9,10-secocholesta-5(10) ,6,8- trien-1,3,25-triol is converted to 201702 [la,33,5Z,7E,24S]-24-fluoro-9,10-secocholesta-5,7,10-(19)-trien-l,3,25-triol (la,2 5-dihydroxy-2 4S-fluorochole-calciferol), [a]23 +45° (c = 0.1, CH^OH).

B. The starting secocholestane can be preapred in a manner similar to that described in Example IB starting from [la,33]-l,3-bis[(tetrahydro^2H-pyran-2-yl)oxyIpregn-5-en-21-oic acid ethyl ester via the following intermediate) tes: [la,3(3,24S]-l,3-bis[ (tetr ahydro-2H-pyran-2-yl) oxy ]-25-(1-ethoxyethoxy)-24-fluorocholest-5-en-21-oic acid ethyl ester [la,33,24S]-l,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]- 2 5-(1-ethoxyethoxy)-2 4-fluorocholest-5-en-21-ol, [la,33,24S]-l,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-2 5-(1-ethoxyethoxy)-24-fluorocholest-5-en-21-ol 21-(4-methylbenzenesulfonate), 20 [la# 33,24S]-1,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]- -(1-ethoxyethoxy)-24-fluoro-21-iodocholest-5-ene, [la,33,24S]-l,3-bis[(tetrahydro-2H-pyran-2-yl)oxy]-25-(1-ethoxyethoxy)-24-fluorocholest-5-ene, [la,33,24S]-2 4-fluorocholest-5-en-l,3,25-triol, 25 [la,33,24S]-24-fluorocholest-5-en-l,3,25-triol 1,3- di acetate, [la,33,7£,24S]-7-bromo-2 4-fluorocholest-5-en-1,3,25-triol 1,3-diacetate, [la,33,24S]-24-fluorocholesta-5,7-dien-l,3,25-triol 30 1 3-diacetate, ' I [la,33,6Z,24S]-24-fluoro-9,10-secocholesta-5(10),6,8-trien-1,3,25-triol 1,3-diacetate.

C. The intermediate, 4-(1-ethoxyethoxy)-3S-fluoro-1-iodo- 2 2 4-methylpentane, Co.] -38° (c = 1, CHCl^), can be prepared in a manner similar to that described in Example lc starting from 1702 (+)-2R-hydroxy-4-butyrolactone via the following compounds: 2S-fluoro-4-butyrolactone, [a]23 -51° (c = 0.9, 5 CHC13), 4-methyl-3S-fluoro-1,4-pentanediol, [a]22 -40° (c = 1, CHC1-.) , 22 4-methyl-3S-fluoro-1,4-pentanediol 1-acetate, -49° (c = 0.5, CHC13), 10 4-(1-ethoxyethoxy)-3S-fluoro-4-methyl-1-pentanol 1-acetate, 4-(1-ethoxyethoxy)-3S-fluoro-4-methy1-1-pentanol, [a]22 -16° (c = 1, CHCl3), 4-(1-ethoxyethoxy)-3S-fluoro-4-methy1-1-pentanol 15 1-(4-methylbenzenesulfonate) .

Example 3 Capsules are manufactured by dissolving the ingredient 20 1,3 and 4 into ingredient 2 under nitrogen and by encapsulating.

Ingredients mg/capsule 1. la,25-dihydroxy-24R- fluorocholecalciferol 0.00010 0.00025 0.00050 0.00100 2. polyethylene glycol 400 200.00 200.00 200.00 200.00 3. butylated hydroxy anisole 0.100 0.100 0.100 0.100 4. ascorbyl palmitate 1.00 1.00 1.00 1.00 Example 4 A solution for intramuscular injection is prepared by 35 dissolving ingredient 1 in 2 under nitrogen. 1. 2. la,2 5-dihydroxy-2 4R-fluorocholecalciferol 95% ethanol - 5% water 0.10 mg 0.50 mg 2.00 ml 3.00 ml 1.00 mg 3.00 ml 201702

Claims (10)

WHAT WE CLAIM IS:

1. A cholecalciferol derivative of formula f

2. The compound of claim 1 which is la,25-dihydroxy--(24R or 24S)-fluorocholecalciferol.

3. A compound according to claim 1 or 2, suitable for use as a pharmaceutically active substance.

4. A compound according to claim 1 or 2, suitable for use as an active substance for increasing the serum calcium and phosphate concentrations and the deposition of these minerals in bones.

5. A process for the manufacture of a compound according to claim 1, which comprises thermally • to? F fix. * .!? , V M •-4* - 29 - 201702 isomerising a precholecalciferol derivative of the formula 10 IIA

6. A medicament containing a compound as in claim 1.

7. A medicament as in claim 6 for increasing the serum calcium and phosphate concentrations as well as the deposition of these minerals in bones.

8. The use of the compound in 24R-form according to Claim 1, for the treatment of milk fever in pregnant ruminant animals.

9. A precholecalciferol derivative of the formula - 30 - 201702 wherein R® is hydrogen or lower alkanoyl.

10. A compound of the group consisting of [la,33,6Z,(24R or 24S)]-24-fluoro-9,10-secocholesta-5 (10) , 6, 8-triene-l, 3,-25-triol 1,3-diacetate and [la, 3 3,6Z , (24R or 24S)]-24-fluoro-9,10-secocholesta-5 (10),6,8-triene-l,3,25-triol. OATB9 THIS ^ DAY OF ^ |l 1>f A. J. PARK, * SON re* sJ , AGENTS FOft fHC AFTUCAMTS