Salts and crystal forms of omecamtiv mecarbil

An omecamtiv mecarbil tartrate crystalline salt form which is any one of the following forms:

• i) an omecamtiv mecarbil bis-tartrate crystalline salt form A, characterized by an X-ray powder diffraction (XRPD) pattern comprising peaks at 4.20, 7.49, 8.22, 11.88, 16.42, and 21.19±0.2° 2θ using Cu Kα radiation;
• ii) an omecamtiv mecarbil bis-tartrate crystalline salt form B, characterized by an X-ray powder diffraction (XRPD) pattern comprising peaks at 3.77, 5.69, and 10.07±0.2° 2θ using Cu Kα radiation;
• iii) an omecamtiv mecarbil bis-tartrate crystalline salt form C, characterized by an X-ray powder diffraction (XRPD) pattern comprising peaks at 3.57, 6.23, and 15.84±0.2° 2θ using Cu Kα radiation;
• or
• iv) an omecamtiv mecarbil mono-tartrate crystalline salt form D, characterized by an X-ray powder diffraction (XRPD) pattern comprising peaks at 9.77 and 15.40±0.2° 2θ using Cu Kα radiation.