Chemical & pharmaceutical bulletin最新文献

Density functional theory calculations on the cyclization of di-t-butyl 2-(2-aminophenyl)-2-methyl malonate (1) to t-butyl 3-methyloxindole-3-carboxylate (2) reveal that acetic acid-assisted protonation of the carbonyl oxygen atom reduces the activation Gibbs free energy significantly lower than methanol-assisted pathways. Experimental data confirm that reaction concentration plays a pivotal role in oxindole formation. Experimental results also indicate distinct reaction mechanisms at low and high concentrations. Achieving high enantioselectivity for chiral compound 2 in high-concentration reactions requires discovering a novel chiral acid.

3-Acetyl-11-keto-β-boswellic acid is a pentacyclic triterpenoid. It is found in frankincense, which is the resin found in plants from the Boswellia genus. Single crystals of 3-acetyl-11-keto-β-boswellic acid methanol and acetonitrile solvates were obtained from the Boswellia serrata extract. X-Ray crystal structure analysis revealed the coexistence of a brominated derivative, 3-acetyl-11-keto-12-bromo-β-boswellic acid. Mass spectroscopy analysis confirmed the presence of the brominated derivative in the extract. These results provide a structural basis for insights into the chemical reactivity and possibly the biosynthesis of 3-acetyl-11-keto-β-boswellic acid and its related substances in B. serrata.

This study investigates the influence of needleless versus needle-based electrospinning methods on the fiber diameter of polyamide 6 (PA6) nanofibers under comparable conditions, with an emphasis on potential pharmaceutical applications. Additionally, it examines how varying solvent systems impact fiber diameter specifically in needleless electrospinning. In this study, it was found that fibers produced by the needleless method were thicker compared to those produced by the needle-based method, a trend attributable to the specific solution characteristics and parameter settings unique to this study. Notably, a 2 : 1 acetic acid : formic acid solvent mixture yielded the largest fiber diameters among the solvent systems assessed for needleless electrospinning. These results underscore the potential of PA6 nanofibers in pharmaceutical applications, suggesting that further optimization of electrospinning conditions could enhance their suitability. The study also discusses the implications of scale-up production using needleless technology, highlighting its viability for industrial applications over single-needle electrospinning.

The pharmaceutical industry relies heavily on the safe and efficient packaging of drugs and injection glass vials play a pivotal role in this regard. Ensuring the quality and consistency of these vials is essential for safeguarding the potency of pharmaceutical formulations. In this study, the recent breakthroughs achieved in the manufacturing of injection glass vials by implementing advanced surface-processing technologies were examined. We developed potential injection glass vials using the novel vial-inner-surface treatment (VIST) technology to homogenize the inner surface of the vials. Compared with common vials, the elution of alkali contents and conductivity of these injection glass vials were reduced because of the VIST technology, resulting in the formation of smooth and homogeneous inner surfaces. In addition, drug adsorption onto the inner surface of the VIST vials was considerably lowered than that onto common vials. These results suggest that VIST vials are of excellent quality and could become the standard injection glass vials.

In the present study, magnetic-calcined bamboo composite adsorbents (MCBC200, MCBC400, MCBC600, MCBC800, and MCBC1000) were prepared, and their physicochemical characteristics (scanning electron microscope images, differential thermogravimetric analysis, Fourier transform-IR, specific surface area, surface functional groups, and point of zero charge [pH_pzc]) were evaluated. Furthermore, the adsorption capacity of methylene blue (MB, cationic dye) using the prepared adsorbents was assessed. The value of pH_pzc and the specific surface area of MCBC400 were 7.8 and 50.6 m²/g, respectively. The amounts of acidic or basic functional groups of MCBC400 were relatively greater than those of the other adsorbents. The amount of MB adsorbed onto MCBC400 (31.9 mg/g) was higher than that onto other adsorbents. The adsorption of MB using MCBC400 was evaluated in relation to various parameters, including coexistence, solution pH, adsorption temperature, and contact time. The results followed the Langmuir isotherm model and a pseudo-second-order model with correlation coefficients of 0.980-1.000 and 0.996, respectively. MB was selectively adsorbed by MCBC400 in a binary solution system containing anionic dyes. Finally, one of the adsorption mechanisms was determined by analyzing the elemental distribution and the binding energy before and after the adsorption of MB. The current findings provide important information for removing MB with MCBC400 from the aqueous phase.

The wearing of medical gowns during anticancer drug preparation is recommended for the prevention of drug exposure. Non-breathable and breathable gowns (gown- and gown+, respectively) are both available. However, anticancer drugs may permeate "gown+." In the present study, water, hydrophilic and lipophilic dyes, and aqueous solutions of several model chemicals with different physical properties (pyridoxine, antipyrine, ethyl p-hydroxybenzoate, and butyl p-hydroxybenzoate) were applied to four types of gowns and their chemical permeabilities were measured. The permeability of gowns to vaporized ethanol was also investigated because several volatile anticancer drugs are currently used in the treatment of cancer. The results obtained showed that the hydrophilic chemical, pyridoxine, did not permeate any of the gowns tested. Furthermore, gowns became more permeable as the lipophilicity of chemicals increased. No significant changes were observed in the chemical permeability between "gown-" and "gown+," suggesting that the protective efficacy of the gowns against permeation by anticancer drugs was similar regardless of breathability. On the contrary, "gown + " was permeable to vaporized ethanol, whereas "gown-" was not. The present study demonstrates the need for safety measures in lipophilic or volatile anticancer drug handling and the importance of developing medical gowns that are highly resistant to chemical permeation.

Co-amorphous materials have gained special attention in the pharmaceutical field due to their high potential to enhance the oral bioavailability of poorly aqueous soluble drugs. In co-amorphous studies, few reports have examined the physical properties and molecular states of different active pharmaceutical ingredients (APIs) : co-amorphous former (CF) molar ratios and preparation methods. Therefore, we investigated the effect of molar ratio and preparation method on the physical properties of a novel co-amorphous system consisting of cilostazol and l-tryptophan, which we identified through screening. Co-amorphous consisting of molar ratios of 1 : 1 (co-milling (CM) 1 : 1), 1 : 1.5 (CM 1 : 1.5), and 1 : 2 (CM 1 : 2) were prepared by the CM method, while samples with a molar ratio of 1 : 1 (spray drying (SD) 1 : 1) were prepared by the spray drying method. CM 1 : 1.5 and CM 1 : 2 showed the highest solubility. Storage stability was excellent for CM 1:1.5, CM 1 : 2, and SD 1 : 1, whereas physical properties were improved by co-amorphization. To investigate the factors responsible for the improved physical properties, the molecular state of the co-amorphous system was evaluated, and it was inferred that hydrogen bonds were formed between cilostazol and l-tryptophan. Solid-state ¹³C-NMR showed several new peaks specific to the solid state in the co-milled sample compared to SD 1 : 1 and cilostazol amorphous, suggesting that the molecular state may differ depending on the preparation method. As described above, different physical properties and molecular states were observed in the novel co-amorphous system consisting of cilostazol and l-tryptophan when the molar ratio of APIs and CF, and the preparation method differed.

Peptides that contain unusual motifs, such as non-proteinogenic amino acids (AAs) and/or macrocyclic substructures, have recently attracted great attention as a new modality in medium-sized-molecule drug discovery. Therefore, it is highly important to develop methods for the chemical synthesis of a wide variety of such unusual peptide derivatives, which are often difficult to prepare via conventional synthetic approaches. In this review, the development of unconventional approaches for the synthesis of unusual peptide derivatives is discussed. Specifically, a novel external-oxidant-mediated decarboxylative condensation of α-ketoacids that can be applied to the synthesis of a wide variety of unusual peptide derivatives is reported. Moreover, an organocatalytic asymmetric Mannich-type addition is discussed that provides chiral β-amino-α-ketoacids, which are required as starting materials for the decarboxylative condensation. In this reaction, the adducts corresponding to various unusual AA side chains are obtained in high yield and excellent stereoselectivity. Furthermore, the "N-chloropeptide strategy" is proposed as a new method for the chemical modification of peptides without the need for a reactive AA residue.