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Morniflumate diniflumate, a molecular compound involving niflumic acid and its β-morpholino ethyl ester (morniflumate) in the mole ratio 2:1, is found to crystallize in a triclinic P - 1 space group with a unit-cell volume of 2203.4(5) Å 3 . It is a cocrystal between a morniflumate + niflumate - salt and a neutral niflumic acid molecule. The co-crystalline salt forms endothermically with a positive excess volume and it melts incongruently at 382.3(8) K. Differential scanning calorimetry executed at heating rates above 20 K⋅min -1 , leads to congruent melting at 387.8(9)K with an enthalpy change of Δ fus H = 80(2) J g -1 . The rare occurrence that incongruent and congruent melting can be observed for the same cocrystal may be due to the conformational versatility of the niflumic acid molecule and its slow conversion between the different conformations due to weak intramolecular hydrogen bonding., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aging of drug molecules is generally studied following regulatory procedures, i.e. under forced conditions and for relatively limited storage time; therefore naturally aged samples are rare and provide scientific reference data beyond regulatory considerations. Tienoxolol was studied after 25 years of storage in the dark under ambient conditions. About 86% of the samples still consisted of tienoxolol and the main impurity (13%) was caused by the hydrolysis of the ester moiety. Protection from humidity is therefore important. Other sensitive groups containing nitrogen and sulfur appear to be quite stable with less than 0.8% conversion over 25 years. In addition, the crystal structure has been solved. Tienoxolol orange needles were found to crystallize in the orthorhombic non-centrosymmetric space group Iba2, indicating that the crystal is a racemic compound. The unit cell parameters at room temperature are a=10.069(5)Å, b=45.831(10)Å, and c=9.822(5)Å and the unit cell volume is 4533(3)Å(3) with Z=8., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Two new saponins were isolated from Mimosa tenuiflora and their structures established as 3-O-[alpha-L-rhamnopyranosyl(1----2)-beta-D-glucopyranosyl-(1----3]-(alp ha-L- arabinopyranosyl-(1----4]-beta-D-xylopyranosyl-(1----2)]-[beta-D- xylopyranosyl-(1----4)]-beta-D-glucopyranosyl)-28-O-alpha-L-rhamnopyrano syl oleanolic acid and 3-O-[alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranosyl-(1----3]-(al pha- L-arabinopyranosyl-(1----4]beta-D-xylopyranosyl-(1----2)]-[beta-D- xylopyranosyl-(1----4)]-beta-D-glucopyranosyl) oleanolic acid.