Patent EA-000301-B1 (EA)
Title: Anhydrous crystals
Inventor: SATO YUKIO
IPC: C07D207/27
Filed: 1996-03-01
Abstract: 1. Anhydrous crystals of compounds represented by the general formula: R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl, characterized in that said crystal essentially not possess hygroscopicity. 2. Crystals of Claim 1, characterized in that said crystals yield a weight gain of at most 1 % after storage at a relative humidity of 83 % and a temperature of 25 degree C for 30 days. 3. Cryctals of Claim 1 or 2 characterized in that the compound represented by the following formula   4. Method of obtaining anhydrous crystals of compounds represented by the general formula: R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl, characterized in that said crystal essentially not possess hygroscopicity comprising a step of drying the hydrous crystals of the above compounds at a temperature of 80 degree C or above under reduced pressure. 5. Method of obtaining anhydrous crystals of Claim 3, characterized in that said crystals yield a weight gain of at most 1 % after storage at a relative humidity of 83 % and a temperature of 25 degree C for 30 days. 6. Method of Claims 4 or 5 comprising a step of drying the hydrous crystals of the above compounds. 7. Method of Claims 6, characterized in that water content in anhydrous crystals comprises 20% or less. 8. Method of any 4-7 Claims, characterized in that the drying stage is carried out at temperature between 110 and 120 degree C. 9. Method of any 4-8 Claims, characterized in that the reduced pressure is 50 mm mercury column or less. 10. Method of any 4-9 Claims, characterized in that the compound represented by the following formula   11. Anhydrous crystals of compounds represented by the general formula: R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl, characterized in that said crystal essentially not possess hygroscopicity obtained by a method, comprising the drying step of the hydrous crystals of the above compounds at temperature at least 80 degree C and reduced pressure. 12. Crystals of Claim 11, characterized in that yield a weight gain of at most 1 % after storage at a relative humidity of 83 % and a temperature of 25 degree C for 30 days. 13. Crystals of Claim 11 or 12, characterized in that said compound represented by the following formula   14. Use of crystals by any of 1-3 Claims to obtain medicines, containing as an active ingredient said compounds, represented by the formula R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl. 15. Crystal by any of 1-3 Claims, useful for preparing medicines containing as an active ingredient said compounds, represented by the formula R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl. 16. Medicines, obtaining activity to increase perceiving ability containing as an active ingredient said compounds, represented by the formula R<2>-CH2CONH-R<1> wherein R<1> represents (un)substituted pyridyl or (un)substituted phenyl; and R<2> represents (un)substituted 2-oxo-1-pyrrolidinyl.