Agomelatine co-crystals with resorcinol and hydroquinone: Preparation and characterization

Lee, Min-Jeong; Chun, Nan-Hee; Kim, Hyo Cheol; Kim, Moon-Jip; Kim, Paul; Cho, Minyong; Choi, Guang J.

doi:10.1007/s11814-017-0347-z

Cited by 6 publications

(5 citation statements)

References 32 publications

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“…Therefore, it can be inferred that the endothermic event at ∼42 °C indicates a solid to solid-state structural phase transition (solid-state phase transition). It is interesting to note similar thermal behavior of other reported M-APIs systems with AGL as one of its components, e.g., AGL–hydroquinone (1:1), AGL–acetic acid (1:1), , and AGL–resorcinol (2:1) . This small endotherm before melting is a clear indication of an enantiotropic solid-state phase transition that is not very commonly observed in molecular crystals because these are associated with relatively high energy barriers due to hindered molecular rearrangement …”

Section: Resultssupporting

confidence: 66%

“…It is interesting to note similar thermal behavior of other reported M-APIs systems with AGL as one of its components, e.g., AGL−hydroquinone (1:1), 31 AGL−acetic acid (1:1), 30,31 and AGL−resorcinol (2:1). 32 This small endotherm before melting is a clear indication of an enantiotropic solid-state phase transition that is not very commonly observed in molecular crystals because these are associated with relatively high energy barriers due to hindered molecular rearrangement. 22 In general, the mechanism of solid-state phase transition is mainly dictated by the structural closeness/differences between parent and daughter phases.…”

Section: Discovery Of Polymorphism and Their Thermalmentioning

confidence: 99%

“…This molecule contains amide functionality that is conventionally nonionizable, but it has the potential to act as a hydrogen bonding donor and acceptor . This molecule has a versatile solid-state structural landscape − containing polymorph, cocrystal, salt, and polymorph of cocrystal. A detailed literature survey was carried out for all agomelatine M-APIs.…”

Section: Introductionmentioning

confidence: 99%

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Solid-State Phase Transition of Agomelatine–Phosphoric Acid Molecular Complexes along the Salt–Cocrystal Continuum: Ab Initio Powder X-ray Diffraction Structure Determination and DFT-D2 Analysis

Voguri

Ranga

Dey

et al. 2020

Crystal Growth & Design

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The solid-state phase transition of a multicomponent active pharmaceutical ingredient (M-APIs), composed of (1:1) agomelatine and phosphoric acid (AGL-P), is characterized using a set of complementary techniques: in situ variable temperature powder X-ray diffraction (VT-PXRD), thermal analysis, spectroscopic techniques, and hot stage microscopy (HSM). It is observed that these dimorphic forms (AGL-P RT-form and HT-form) are enantiotropic and reversible in nature. The salt–cocrystal continuum of this system is demonstrated using ab initio powder XRD structure determination (SDPD) and dispersion corrected density functional theory (DFT-D2) analysis. Furthermore, this solid-state phase transition can be inferred as a martensitic-like transformation, where simultaneous proton migration and small conformational switching trigger the concerted molecular displacements of entire layers, leading to microscopic crystal contraction.

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Section: Resultssupporting

confidence: 66%

Section: Discovery Of Polymorphism and Their Thermalmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Solid-State Phase Transition of Agomelatine–Phosphoric Acid Molecular Complexes along the Salt–Cocrystal Continuum: Ab Initio Powder X-ray Diffraction Structure Determination and DFT-D2 Analysis

Voguri

Ranga

Dey

et al. 2020

Crystal Growth & Design

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“…In fact, some of us have studied this coformer in other crystal engineering studies [25,26], with the results demonstrating its remarkable ability to improve the stability of vitamin D 3 via cocrystallization [27]. Resorcinol has also been previously utilized to prepare cocrystals with agomelatine [28], curcumin [29], and Ciprofloxacin, a fluoroquinolone antibiotic similar to Norfloxacin [30].…”

Section: Methodsmentioning

confidence: 99%

Synthesis and Characterization of a New Norfloxacin/Resorcinol Cocrystal with Enhanced Solubility and Dissolution Profile

et al. 2021

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A new cocrystal of Norfloxacin, a poorly soluble fluoroquinolone antibiotic, has been synthetized by a solvent-mediated transformation experiment in toluene, using resorcinol as a coformer. The new cocrystal exists in both anhydrous and monohydrate forms with the same (1:1) Norfloxacin/resorcinol stoichiometry. The solubility of Norfloxacin and the hydrated cocrystal were determined by the shake-flask method. While Norfloxacin has a solubility of 0.32 ± 0.02 mg/mL, the cocrystal has a solubility of 2.64 ± 0.39 mg/mL, approximately 10-fold higher. The dissolution rate was tested at four biorelevant pH levels of the gastrointestinal tract: 2.0, 4.0, 5.5, and 7.4. In a first set of comparative tests, the dissolution rate of Norfloxacin and the cocrystal was determined separately at each pH value. Both solid forms showed the highest dissolution rate at pH 2.0, where Norfloxacin is totally protonated. Then, the dissolution rate decreases as pH increases. In a second set of experiments, the dissolution of the cocrystal was evaluated by a unique dissolution test, in which the pH dynamically changed from 2.0 to 7.4, stepping 30 min at each of the four biorelevant pH values. Results were quite different in this case, since dissolution at pH 2 affects the behavior of Norfloxacin at the rest of the pH values.

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“…It was approved for treatment of depression and marketed as Valdoxan or Thymanax in Europe (de Bodinat et al, 2010). Because AGO has poor water solubility, diverse solid forms of AGO have been investigated to increase its solubility (Zheng et al, 2011;Zhang et al, 2016;Du et al, 2013;Skořepová et al, 2016;Yan et al, 2012;Lee et al, 2018). Among the reported cocrystals, AGO-hydroquinone (AGO-HYQ, see Scheme 1) cocrystal has been reported to exist in two polymorphic forms [forms (I) and (II)] and it was suggested that the two polymorphs are monotropic with the higher melting form (II) being the stable form at room temperature (297 K) (Prohens et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Agomelatine–hydroquinone (1:1) cocrystal: novel polymorphs and their thermodynamic relationship

Lee

Aitipamula

Choi

2019

Acta Crystallogr Sect B

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Polymorphism of active pharmaceutical ingredients (APIs) is of significance in the pharmaceutical industry because it can affect the quality, efficacy and safety of the final drug product. In this regard, polymorphic behavior of cocrystals is no exception because it can influence the development of cocrystals as potential drug formulations. The current contribution aims to introduce two novel polymorphs [forms (III) and (IV)] of agomelatine–hydroquinone (AGO‐HYQ) cocrystal and to describe the thermodynamic relationship between the cocrystal polymorphs. All polymorphs were characterized using powder X‐ray diffraction, differential scanning calorimetry, hot‐stage microscopy and solubility measurements. In addition, the crystal structure of form (II), which has been previously solved from powder diffraction data [Prohens et al. (2016), Cryst. Growth Des.16, 1063–1070] and form (III) were determined from the single‐crystal X‐ray diffraction data. Thermal analysis revealed that AGO‐HYQ cocrystal form (III) exhibits a higher melting point and a lower heat of fusion than those of form (II). According to the heat of fusion rule, the polymorphs are enantiotropically related, with form (III) being stable at higher temperatures. Our results also show that the novel form (IV) is the most stable form at ambient conditions and it transforms into form (II) on heating, and therefore, the two polymorphs are enantiotropically related. Furthermore, solubility and van't Hoff plot results suggest that the transition points are approximately 339 K for the pair form (IV)–(II) and 352 K for the pair form (II)–(III).

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Agomelatine co-crystals with resorcinol and hydroquinone: Preparation and characterization

Cited by 6 publications

References 32 publications

Solid-State Phase Transition of Agomelatine–Phosphoric Acid Molecular Complexes along the Salt–Cocrystal Continuum: Ab Initio Powder X-ray Diffraction Structure Determination and DFT-D2 Analysis

Solid-State Phase Transition of Agomelatine–Phosphoric Acid Molecular Complexes along the Salt–Cocrystal Continuum: Ab Initio Powder X-ray Diffraction Structure Determination and DFT-D2 Analysis

Synthesis and Characterization of a New Norfloxacin/Resorcinol Cocrystal with Enhanced Solubility and Dissolution Profile

Agomelatine–hydroquinone (1:1) cocrystal: novel polymorphs and their thermodynamic relationship

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