Form of N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine
AssigneeBiocon Limited
InventorsShanmughasamy Rajamahendra, Chandrashekhar Aswathanarayanappa, Tom Thomas Puthiaparampil, Madhavan Sridharan, Sambasivam Ganesh
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Abstract
The present invention relates to a novel crystalline form of N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine and methods for preparing the same.
Claims16
Crystalline form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine having at least two of the following properties:
- (a) a melting point in the range of 126° to 132° C.;
- (b) a powder X-ray diffraction pattern comprising characteristic peaks at 14.0, 17.8, 19.0, 20.2 and 21.2+0.2 degrees measured at reflection angle 2θ;
- and
- (c) an infrared absorption spectrum comprising absorption bands in the region of 1742, 1648, 1599, 1540 and 1191+2 cm−1.
Crystalline form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine having at least one of the following properties:
- (a) a powder X-ray diffraction pattern in accordance with FIG. 1;
- and
- (b) an infrared absorption spectrum in accordance with FIG. 2.
A process for preparing form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine comprising the steps of:
- (a) suspending N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine methyl ester in water or a water miscible solvent;
- (b) treating the suspension with a base;
- (c) adding water followed by adjusting the pH to 1.0-4.0 using a mineral acid;
- (d) extracting using ethyl acetate;
- (e) concentrating the ethyl acetate extract;
- (f) adding petroleum ether to the ethyl acetate concentrate;
- and
- (g) filtering and drying the resulting precipitate to get form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine.
Crystalline form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine having at least two of the following properties:
- (a) a melting point in the range of 126° to 132° C.;
- (b) a powder X-ray diffraction pattern comprising characteristic peaks at 14.0, 17.8, 19.0, 20.2 and 21.2+0.2 degrees measured at reflection angle 2θ;
- and
- (c) an infrared absorption spectrum comprising absorption bands in the region of 1742, 1648, 1599, 1540 and 1191+2 cm−1;
- obtained by the process of:
- (i) suspending N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine methyl ester in water or a water miscible solvent;
- (ii) treating the suspension with a base;
- (iii) adding water followed by adjusting the pH to 1.0-4.0 using a mineral acid;
- (iv) extracting using ethyl acetate;
- (v) concentrating the ethyl acetate extract;
- (vi) adding petroleum ether to the ethyl acetate concentrate;
- and
- (vii) filtering and drying the resulting precipitate to get form “C” N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine.
Dependencies are inferred from the claim text.