This paper presents an industrial scale process for extraction, purification, and isolation of epiisopiloturine (EPI) (2(3H)-Furanone,dihydro-3-(hydroxyphenylmethyl)-4-[(1-methyl-1H-imidazol-4-yl)methyl]-, [3S-[3a(R*),4b]]), which is an alkaloid from jaborandi leaves (Pilocarpus microphyllus Stapf). Additionally for the first time a set of structural and spectroscopic techniques were used to characterize this alkaloid. EPI has shown schistomicidal activity against adults and young forms, as well as the reduction of the egg laying adult worms and low toxicity to mammalian cells (in vitro). At first, the extraction of EPI was done with toluene and methylene chloride to obtain a solution that was alkalinized with ammonium carbonate. The remaining solution was treated in sequence by acidification, filtration and alkalinization. These industrial procedures are necessary in order to remove impurities and subsequent application of the high performance liquid chromatography (HPLC). The HPLC was employed also to remove other alkaloids, to obtain EPI purity higher than 98%. The viability of the method was confirmed through HPLC and electrospray mass spectrometry, that yielded a pseudo molecular ion of m/z equal to 287.1 Da. EPI structure was characterized by single crystal X-ray diffraction (XRD), 1H and 13C nuclear magnetic resonance (NMR) in deuterated methanol/chloroform solution, vibrational spectroscopy and mass coupled thermal analyses. EPI molecule presents a parallel alignment of the benzene and the methyl imidazol ring separated by an interplanar spacing of 3.758 Å indicating a π-π bond interaction. The imidazole alkaloid melts at 225°C and decomposes above 230°C under air. EPI structure was used in theoretical Density Functional Theory calculations, considering the single crystal XRD data in order to simulate the NMR, infrared and Raman spectra of the molecule, and performs the signals attribution.

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Mechanochemistry synthesis was applied to the supramolecular synthesis and green scale-up production of a 1:1 drug–drug cocrystal involving the antimetabolite prodrug 5-Fluorocytosine (5-FC) and the tuberculostatic drug Isoniazid (INH), namely, 5FC-INH. Crystalline material, also obtained by traditional slow evaporation methods, was analyzed by single-crystal X-ray diffraction (XRD). The crystal packing is stabilized by a classical N–H···N hydrogen-bond interaction between the amine moiety of 5-FC and the INH pyridine nitrogen. IR and Raman data provided spectroscopic evidence about the hydrogen atom positions, thereby confirming the neutral nature of the cocrystal. Furthermore, 5FC-INH codrug was also evaluated by a range of analytical techniques such as powder XRD and thermal (thermogravimetric analysis, differential scanning calorimetry, hot stage microscopy) analyses. A physical stability study was performed in high relative humidity conditions to verify possible 5-FC solid-state hydration and/or INH degradation. The equilibrium solubility of this codrug was compared to the anhydrous 5-FC and INH raw materials, in pH 1.2 buffer media, and it was found to be similar to that of 5-FC, a biopharmaceutics classification system class I drug. The results show that the cocrystal has superior phase stability properties against moisture when compared to the starting pharmaceutical ingredients, so it could be considered as a potential candidate for the treatment of concomitant fungal infections, tuberculosis, and cancer.