BACKGROUND OF THE INVENTION US 5, 216, 167 discloses 2-ethoxy-4-{[3-methyl-1-(2-piperidin- I-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid. The compound exhibits blood-glucose lowering action with lower toxicity and may be safely administered, orally or parenterally, as it is or advantageously as a pharmaceutical composition comprising an effective amount of the compound or its pharmacologically acceptable salt and a pharmacologically acceptable carrier, excipient or diluent therefor, in the form of powder, granule, tablet, hard capsule, soft capsule, dry syrup, suppository, injection or the like.

US 6,143, 769 discloses (S)-(+)-2-ethoxy-4-{[3-methy1-1-(2- piperidin-1-yl-phenyl)-butylcarbamoyl]-methyl}-benzOic acid which is currently marketed for treatment of Type II diabetes.

The present invention discloses a novel salt of 2-ethoxy-4- {[3-methyl-1-(2-piperidin-1-yl-phenyl)-butylcarbamoyl]-methy l}- benzoic acid or (S)-(+)-2-ethoxy-4-{[3-methyl-t-(2-piperidin-1-yl-

phenyl)-butylcarbamoyl]-methyl-benzoic acid namely phosphoric acid salt of 2-ethoxy-4-{[3-methyl-1-(2-piperidin-1-yl-phenyl)- butylcarbamoyl]-methyl-benzoic acid or phosphoric acid salt of (S)-(+)-2-ethoxy-4-{[3-methyl-1-(2-piperidin-1-yl-phenyl)- butylcarbamoyl]-methyl}-benzoic acid (FORMULA I) which is useful in treatment of Type II diabetes. This compound shows good stability in solid form. Also this compound is significantly more soluble in water or aqueous media than (S)-(+)-2-ethoxy-4-{[3- methyl-t-(2-piperidin-t-yl-phenyl)-butylcarbamoyl]-methyl}- benzoic acid.

SUMMARY OF THE INVENTION The present invention relates to a novel compound of formula I, which is phosphoric acid salt of 2-ethoxy-4-{[3-methyl-1- (2-piperidin-1-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid or phosphoric acid salt of (S)-(+)-2-ethoxy-4-{[3-methyl-1-(2- piperidin-1-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid (FORMULA I), to a process for preparing this novel compound, to a pharmaceutical composition containing this compound and to the prophylactic and/or therapeutic use of the compound and composition.

FORMULA I

The present invention provides a compound of formula I, for use in the treatment of and/or prophylaxis of hyperglycemia.

The stability and solubility of this compound in water/aqueous media provides for significant advantages in formulation, bioavailability and bulk handling.

DETAILED DESCRIPTION OF THE INVENTION Accordingly, the present invention provides a novel compound of formula I.

FORMULA I The compound of formula I is a phosphoric acid salt of 2- <BR> <BR> ethoxy-4-{[3-methyl-1-(2-piperidin-t-yl-phenyl)-butylcarbamo yl]- methyl}-benzoic acid or phosphoric acid salt of (S)- (+)-2-ethoxy-4- <BR> <BR> [3-methyl-l- (2-piperidin-1-yi-phenyl)-butylcarbamoyl]-methyll- benzoic acid.

As stated the compound of the invention is significantly more soluble in water/aqueous media than the corresponding free base.

A convenient method for determining the stability of the compounds of the invention in aqueous solution involves determining the degree of precipitation of the parent free base from an aqueous solution of the test compound at known

conditions of temperature and over known periods of time. We have found that the compound of formula I show good stability in aqueous conditions.

The currently marketed (S)-(+)-2-ethoxy-4-{[3-methyl-1-(2- piperidin-1-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid is insoluble in water (The Merck Index Online, 2003). The compound of present invention is significantly soluble in water. This has important pharmacokinetic advantage and enhances bioavailabitity.

The quantitative analysis of the test may be carried out using conventional methods e. g. HPLC.

As mentioned above the compound of the invention is indicated as having useful therapeutic properties.

The present invention accordingly provides a compound of formula I, for use as an active therapeutic substance.

Thus the present invention provides a compound of formula I, for use in the treatment of and/or prophylaxis of hyperglycemia.

Accordingly, the present invention also provides a pharmaceutical composition comprising a compound of formula I and a pharmaceutical acceptable carrier therefor.

Usually the pharmaceutical compositions of the present invention will be adapted for oral administration, although compositions for administration by other routes, such as by injection and percutaneous absorption are also envisaged.

Particularly suitable compositions for oral administration are unit dosage forms such as tablets and capsules. Other fixed unit

dosage forms, such as powders presented in sachets, may also be used.

The present invention further provides a method for the treatment and/or prophylaxis of hyperglycemia in a human or non- human mammal, which comprises administering an effective, non- toxic, amount of a compound of formula I, , to a hyperglycemic human or non-human mammal in need thereof.

The reaction between (S)-(+)-2-ethoxy-4-{[3-methyl-1-(2- piperidin-t-yl-phenyl)-butylcarbamoyl]-methyl}-benzOic acid and the source of phosphoric acid counter-ion is generally carried out under conventional salt forming conditions, for example by admixing 2-ethoxy-4-{[3-methyl-1-(2-piperidin-1-yl-phenyl)- butylcarbamoyl]-methyl}-benzoic acid and the source of counter- ion, phosphoric acid, in approximately equimolar amounts but preferably using an excess of the source of counter-ion, phosphoric acid, in a solvent, generally a C1-4 alkanolic solvent such as methanol, ethanol, or other aprotic solvents like acetonitrile, at any temperature which provides a suitable rate of formation of the required product, generally at an elevated temperature and thereafter isolating the product.

The following Example illustrates the invention but does not limit it in any way.

EXAMPLES Example 1 To a solution of (S)-(+)-2-ethoxy-4-{[3-methyl-1-(2-piperidin- 1-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid (5 g, 0.009 mol) in methanol (50 ml), phosphoric acid (85%, 0.7 g) was added.

After stirring for 30 minutes, the reaction mixture was concentrated to about 10 ml and chilled. Filtration of the mixture afforded title compound.

Example 2 To a solution of 2-ethoxy-4-{[3-methyl-1-(2-piperidin-1-yl- phenyl)-butylcarbamoyl]-methyl}-benzoic acid (100 g, 0.18 mol) in acetonitrile (500 ml), phosphoric acid (85%, 14 g) was added.

After stirring for 30 minutes, the reaction mixture was concentrated to about 250 mi and chilled. Filtration of the mixture afforded title compound.

Example 3 To a solution of (S) » 2-ethoxy-4-{[3-methyl-1-(2-piperidin- t-yl-phenyl)-butylcarbamoyl]-methyl}-benzoic acid (100 g, 0.18 mol) in isopropyl alcohol (500 ml), phosphoric acid (85%, 14 g) was added. After stirring for 30 minutes, the reaction mixture was concentrated to about 250 ml and chilled. Filtration of the mixture afforded title compound.