Novel polymorphic forms of cipamfylline

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits an infrared absorption spectrum in potassium bromide having characteristic absorption bands expressed in reciprocal centimeters as described in FIG. 20.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that that exhibits a single crystal X-ray crystallographic analysis with (a) crystal parameters that are approximately equal to the following:

• 14 Crystal shape (mm) Flat needles Crystal dimensions 1.0 × 0.12 × 0.08 mm Crystal color Colorless Space Group P1 triclinic #2 Temperature 295K Cell Constants a = 10.829 (2) Å b = 12.636 (2) Å c = 5.105 (3) Å alpha (α) = 99.48 (4) beta (β) = 91.53 (4) gamma (γ) = 83.84 (3) Volume 685.0 (8) Å3 Molecules/unit cell (Z) 4 Density, (ρ) g/cm−3 1.354 μ 7.362 cm−1 F (000) 292
• the atomic positions of all atoms relative to the origin of the unit cell as represented in the tables of FIGS. 12 to 15.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits a Raman Spectroscopy pattern as expressed in FIG. 4.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits an X-ray powder diffraction pattern having characteristic peaks expressed in d spacing (A) in decreasing intensity, at approximately 12.001, 6.702, 3.687, 3.773, and 7.345, and as expressed in FIG. 2.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits an infrared absorption spectrum in potassium bromide having characteristic absorption bands expressed in reciprocal centimeters as described in FIG. 21.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits a single crystal X-ray crystallographic analysis with crystal parameters that are approximately equal to the following:

• 15 Crystal Shape (mm):
• Rectangular blocks Space Group P21/c monoclinic #14 Cell Constants a = 12.227 (4) Å b = 7.448 (2) Å c = 14.946 (8) Å beta (β) = 97.95 (4) Volume 1348.1 (9) Å3 Molecules/unit cell (Z) 4 ρ (calc) Density 1.356 g/cm−3 μ 0.896 cm−1 F (000) 584

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits a Raman Spectroscopy pattern as expressed in FIG. 5.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits an infrared absorption spectrum of a crystal having characteristic absorption bands expressed in reciprocal centimeters as described in FIGS. 18, 24 or 25.

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits a single crystal X-ray crystallographic analysis with crystal parameters that are approximately equal to the following:

• 16 Crystal shape (mm) Flat needles Space Group P1 triclinic #2 Cell Constants a = 10.210 (3) Å b = 13.753 (2) Å c = 4.942 (31) Å alpha (α) = 97.94 (2) beta (β) = 97.95 (4) gamma (γ) = 83.33 (2) Volume 677.1 (5) Å3 Molecules/unit cell (Z) 2 Density, g/cm−3 1.350

A crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine that exhibits a Raman Spectroscopy pattern as expressed in FIG. 6.

A process for producing a crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine, Form I, which process comprises

• a) dissolving 1,3-di-cyclopropylmethyl-8-amino xanthine in 1-propanol;
• and
• b) cooling the solution to crystalize out of solution the desired polymorphic Form I.

A process for producing a crystalline polymorph of 1,3-di-cyclopropylmethyl-8-amino xanthine, Form I, which process comprises

• a) dissolving 1,3-di-cyclopropylmethyl-8-amino xanthine in tetrahydrofuran or acetone;
• and
• b) cooling the solution to crystalize out of solution the desired polymorphic Form I.