20.500.12556/RUL-133367 Co-crystals, salts or mixtures of both? The case of tenofovir alafenamide fumarates Tenofovir alafenamide fumarate (TAF) is the newest prodrug of tenofovir that constitutes several drug products used for the treatment of HIV/AIDS. Although the solid-state properties of its predecessor tenofovir disoproxil fumarate have been investigated and described in the literature, there are no data in the scientific literature on the solid state properties of TAF. In our report, we describe the preparation of two novel polymorphs II and III of tenofovir alafenamide monofumarate (TA MF2 and TA MF3). The solid-state structure of these compounds was investigated in parallel to the previously known tenofovir alafenamide monofumarate form I (TA MF1) and tenofovir alafenamide hemifumarate (TA HF). Interestingly, the single-crystal X-ray diffraction of TA HF revealed that this derivative exists as a co-crystal form. In addition, we prepared a crystalline tenofovir alafenamide free base (TA) and its hydrochloride salt (TA HCl), which enabled us to determine the structure of TA MF derivatives using $^{15}$N-ssNMR ($^{15}$N-solid state nuclear magnetic resonance). Surprisingly, we observed that TA MF1 exists as a mixed ionization state complex or pure salt, while TA MF2 and TA MF3 can be obtained as pure co-crystal forms. co-crystal salt polymorphism X-ray diffraction ssNMR tenofovir alafenamide fumarate true false true Angleški jezik Ni določen Članek v reviji 2021-11-24 09:58:30 2021-11-24 09:58:31 2022-09-12 04:16:01 0000-00-00 00:00:00 2020 0 0 21 str. iss. 4, art. 342 Vol. 12 Apr. 2020 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 615 1999-4923 10.3390/pharmaceutics12040342 1569374 RAZ_Lengauer_Hannes_2020.pdf RAZ_Lengauer_Hannes_2020.pdf 1 6C0109C8703ACBEF8083424FF92F68A4 fa1ce12ead7f17f0a3f1c60621c7e49faa899373a40ea209bcc5d576f55f83fd 05c090e8-4d05-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=151381 https://www.mdpi.com/1999-4923/12/4/342 0 fd7de0c9-4d04-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=151380 Fakulteta za kemijo in kemijsko tehnologijo Fakulteta za farmacijo 0 0 0