The orthorhombic form of p-hydroxyacetanilide

Haisa, M.; Kashino, S.; Maeda, Hirokuni

doi:10.1107/s0567740874007473

Cited by 202 publications

(182 citation statements)

References 4 publications

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“…Acetaminophen has been reported with two types of intermolecular hydrogen bonding (Chart 1) which was important to control the stability of different polymorphs. According to the X-ray crystallographic data, 1,2,7,8) the form I acetaminophen exhibited a stronger hydrogen bonding than form II. The distance of NH··O assigned to the type A hydrogen bonding and OH··O assigned to the type B hydrogen bonding in acetaminophen crystal is 2.91 and 2.65Å for form I and 2.97 and 2.72Å for form II, respectively.…”

Section: Resultsmentioning

confidence: 99%

Transformation of Metastable Forms of Acetaminophen Studied by Thermal Fourier Transform Infrared (FT-IR) Microspectroscopy.

2002

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Acetaminophen is still worldwide used for analgesic and antipyretic therapy by millions of tablets and other dosage forms. Two polymorphs of acetaminophen have been published: form I is a monoclinic crystal and form II is an orthorhombic crystal. Form I (the usual form) is more stable at room temperature than form II.1-4) Form I has poor binding and densification properties, 5,6) and is not suitable for direct compression into tablet. The preparation for monoclinic acetaminophen tablets therefore needs a series of time-and material consuming processes and excipients, and the size of the tablets cannot but be enlarged. On the other hand, the orthorhombic acetaminophen not only has a sliding plane for good compression but also shows a faster dissolution rate than the monoclinic form. [6][7][8] Therefore, many studies have focused on how to prepare the orthorhombic form of acetaminophen. [8][9][10] An unstable third modification of acetaminophen (form III) has been found after different crystallization methods and the cooling rates, but the ambiguous explanations due to various differential scanning calorimetry (DSC) curves obtained have caused argument. [8][9][10][11] In the present study, a simple, quick and timesaving tool of Fourier transform infrared (FT-IR) microspectroscopy equipped with a micro hot stage (thermal FT-IR microscopic system) was used to readily and exactly explain the phase transition of metastable forms of acetaminophen by one-step process, as compared with different DSC thermograms of acetaminophen polymorphs prepared by different methods. ExperimentalMaterials Acetaminophen was of pharmaceutical grade, purchased from Seven Star Pharm. Co., Ltd. Taiwan, ROC. It was first recrystallized from aqueous solution, and then stored at 25°C, 75% relative humidity (RH) for further use. KBr crystal was of analytical IR grade, purchased from Jasco Co., Tokyo, Japan.Thermal FT-IR Microspectroscopic Study The acetaminophen powder was sandwiched between two KBr pieces by a hydraulic press to form a disc. This sample disc was directly put on a micro hot stage (DSC microscopy cell, FP 84, Mettler, Switzerland). The cell was then set on the stage of the microscope installed in the FT-IR microscopic spectrophotometer (Micro FTIR-200, Jasco, Tokyo, Japan) with an MCT detector. The system was operated in the transmission mode. The desired sample size for determination was selected and defined by means of an Aperture Through Optical System (ATOS) using microscope. The temperature of DSC microscopy cell was monitored with a central processor (FT80HT, Mettler, Switzerland). The heating rate of DSC assembly was controlled at 3°C/min in ambient conditions. The sample disc was previously equilibrated at the starting temperature (25°C) for about 3 min and then heated to 200°C. The thermal-responsive IR spectra were recorded with respect to the temperature. After the first heating process, the sample disc was cooled to 25°C and then re-heated from 25 to 200°C in the same conditions. Preparation and Determination of Diff...

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Section: Resultsmentioning

confidence: 99%

Transformation of Metastable Forms of Acetaminophen Studied by Thermal Fourier Transform Infrared (FT-IR) Microspectroscopy.

2002

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“…This angle decreases with increase in the torsion angle. The C(1)--N(1) distance is close to that in DL-allantion in spite of the difference in the nature of the C(1) atom, and also to that in acetanilides (Brown, 1966;Haisa, Kashino & Maeda, 1974;Haisa, Kashino, Kawai & Maeda, 1976) irrespective of the torsion angle. (9) 2.14 (13) 147 (11) 147(3) 2.935 (9) 2.10 (8) 154 (7) 149 (2) 3.013 (9) 2.14 (6) 161 (5) 113 (2) The geometry of the urea moiety is close to that found in DL-allantoin.…”

Section: Molecular Structurementioning

confidence: 99%

The crystal and molecular structure of phenylurea

Kashino¹,

Haisa²

1977

Acta Crystallogr Sect B

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“…In addition to being easily controllable, the more stable polymorphic form also complies with requirements described in the Q6A Guide of the International Commission on Harmonization (ICH) for solid form selection (Grant et al, 2004). Kristl et al, 1996;Sohn et al, 2008;Lutker et al, 2011;Tutughamiarso et al, 2012) Acetylsalicylic Acid Analgesic IV 2 I (TSRL inc, 2012; Klein et al, 1994;Vishweshwar et al, 2005;Bond et al, 2011) Ibuprofen Analgesic II 2 I (TSRL inc, 2012;Shankland et al, 1996;Erk et al, 2004;Stone et al, 2009;Derollez et al, 2010) Acetaminophen Analgesic IV 6 I (TSRL inc, 2012;Haisa et al, 1974;Naumov et al, 1998;McGregor et al, 2002;Parkin et al, 2002;Peterson et al, 2002;Fabbiani et al, 2004 (Otsuka et al, 1983;Stephenson et al, 1998;Kennedy et al, 2003;Kasim et al, 2004;Aguiar et al, 2011) Ciprofloxacin Antibiotic III 3 II (hydrate) (TSRL inc, 2012;Turel et al, 2003;Fabbiani et al, 2008;Fabbiani et al, 2009;Fabbiani et al, 2011) Doxycycline Antibiotic IV 2 ‡ (TSRL inc, 2012; Legendre et al, 2012) Erythromycin Antibiotic IV 4 Dihydrate (TSRL inc, 2012;Fukumori et al, 1983;Stephenson et al, 1997;Miroshnyk et al, 2006) Sulfamethoxazole Antibiotic IV 4 III (hemihydrate) (TSRL inc, 2012;…”

Section: Bioequivalence and Bioavailabilitymentioning

confidence: 99%

“…Although the amorphous form is the most soluble form, it exhibits the lowest stability (Haisa et al, 1974;Lowes et al, 1987;Chieng et al, 2009).…”

Section: Polymorphism Definition and General Considerationsmentioning

confidence: 99%

Polymorphism: an evaluation of the potential risk to the quality of drug products from the Farmácia Popular Rede Própria

Santos

Reis

Jacon

et al. 2014

Braz. J. Pharm. Sci.

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Polymorphism in solids is a common phenomenon in drugs, which can lead to compromised quality due to changes in their physicochemical properties, particularly solubility, and, therefore, reduce bioavailability. Herein, a bibliographic survey was performed based on key issues and studies related to polymorphism in active pharmaceutical ingredient (APIs) present in medications from the Farmácia Popular Rede Própria. Polymorphism must be controlled to prevent possible ineffective therapy and/or improper dosage. Few mandatory tests for the identification and control of polymorphism in medications are currently available, which can result in serious public health concerns.Uniterms: Polymorphism. Medicines/quality control. Medicines/solubility. Medicines/bioavailability.O polimorfismo em sólidos é um fenômeno frequente em fármacos e pode levar a problemas na qualidade dos medicamentos por alterar suas propriedades físico-químicas, em especial a solubilidade e, consequentemente, a biodisponibilidade. Nesse trabalho realizou-se levantamento bibliográfico sobre os principais estudos e problemas relacionados ao polimorfismo em fármacos presentes nos medicamentos disponibilizados pela Farmácia Popular do Brasil. O polimorfismo deve ser controlado a fim de evitar possível ineficácia terapêutica e/ou dosagem inapropriada dos medicamentos. Destacamos que são poucos os ensaios obrigatórios para identificação e controle desse fenômeno em medicamentos, o que pode acarretar grande problema de saúde pública. Unitermos:Polimorfismo. Medicamentos/controle de qualidade. Medicamentos/solubilidade. Medicamentos/biodisponibilidade.

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The orthorhombic form of p-hydroxyacetanilide

Cited by 202 publications

References 4 publications

Transformation of Metastable Forms of Acetaminophen Studied by Thermal Fourier Transform Infrared (FT-IR) Microspectroscopy.

Transformation of Metastable Forms of Acetaminophen Studied by Thermal Fourier Transform Infrared (FT-IR) Microspectroscopy.

The crystal and molecular structure of phenylurea

Polymorphism: an evaluation of the potential risk to the quality of drug products from the Farmácia Popular Rede Própria

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