Chem. Pharm. Bull.(オピニオン)

Determination of absolute configuration (AC) is one of the most challenging features in the structure elucidation of chiral natural products, especially those with complex structures. With revolutionary advancements in the area of quantum chemical calculations of chiroptical spectroscopy over the past decade, the time dependent density functional theory (TDDFT) calculation of electronic circular dichroism (ECD) spectra has emerged as a very promising tool. The principle is simply based on the comparison of the calculated and experimental ECD spectra: the more closely they match, the more reliable conclusion for the AC assignment can be drawn. This review attempts to use several examples representing monomeric flavonoids, rotationally restricted biflavonoids, complex hexahydroxydiphenoyl-containing flavonoids, conformationally flexible and restrained sesquiterpenoids, cembrane-africanene terpenoids, dihydropyranocoumarins, alkaloids, and dihydroxanthones to illustrate the applicability of this approach in determining the AC of structurally diverse natural products. The findings clearly indicate that the TDDFT calculation of ECD spectra can quantify the contribution of individual conformers and the interaction of multiple chromophores, making it possible to determine the AC of complex chiral molecules. The calculated electronic transitions and molecular orbitals provide new insight into the interpretation of ECD spectra at the molecular level.

Determination of Absolute Configuration of Natural Products: Theoretical Calculation of Electronic Circular Dichroism as a Tool.

Houttuynoids A-E, Anti-Herpes Simplex Virus Active Flavonoids With Novel Skeletons From Houttuynia Cordata

Phenolic compounds from Origanum vulgare and their antioxidant and antiviral activities

Polyphenols from wolfberry and their bioactivities.

One-pot reactions of aldoses with L-cysteine methyl ester and o-tolyl isothiocyanate yielded methyl 2-(polyhydroxyalkyl)-3-(o-tolylthiocarbamoyl)-thiazolidine-4(R)-carboxylates. Direct HPLC analysis of the reaction mixture and UV detection at 250 nm discriminated D- and L-enantiomers of aldoses. The reaction was applied to the determination of absolute configuration the sugar residues of an aroma precursor.

http://naosite.lb.nagasaki-u.ac.jp/dspace/bitstream/10069/14910/1/CPBul55_899.pdf

Facile Discrimination of Aldose Enantiomers by Reversed-Phase HPLC

Background: The disease behavior in cases of newly diagnosed IIPs has rarely been investigated prospectively. Methods: In JIPS registry, progression-free survival (PFS) and the percentage of cases meeting progressive fibrosing interstitial lung disease (PF-ILD) criteria were longitudinally investigated. PFS was defined as duration without any event of death, an absolute decline of forced vital capacity (FVC) ≥10%, onset of acute exacerbation, or a decline of &gt;50 meters in the 6-minute walk distance. The PF-ILD criteria were defined as: 1) relative annual decline of FVC ≥5%, 2) FVC decline ≥2.5% and worsening of mMRC or CT findings, or 3) worsening of mMRC and CT findings. Results: In 866 cases with IIPs, mean age was 70 years, and mean FVC %predicted was 80%. The most common was IPF (469 cases), followed by unclassifiable IIP. Median PFS of IPF and unclassifiable IIP were 24.2 and 24.6 months, respectively (HR = 0.91 (95%CI: 0.76–1.10), log-rank test: p = 0.345). Three-year progression-free rates for IIPs, IPF, and unclassifiable IIP were 40%, 36%, and 40%, respectively. After 1 and 2 years, 23% and 37% met the PF-ILD criteria for IIPs: 24% and 42% for IPF, and 23% and 39% for unclassifiable IIP. Conclusions: Among newly diagnosed IIP cases, the prognosis of unclassifiable IIP was similar to that of IPF within 3 years. (NCT03041623)&nbsp;

Nationwide prospective registry of idiopathic interstitial pneumonias with central multidisciplinary diagnosis in Japan (JIPS Registry): Analysis of disease progression

Background: We recently proposed that IgG4-positive interstitial pneumonia (IgG4+ IP) differs in clinical characteristics from IgG4-related disease (RD) (ERJ Open Res 2021;7). Aims and objectives: This study aimed to assess and identify the characteristics of patients with IgG4+ interstitial lung disease (ILD) according to the American College of Rheumatology and European League Against Rheumatism classification criteria for IgG4-RD, 2019. Methods: This was a retrospective nationwide multicentre study in Japan. We reviewed 28 patients, who demonstrated ILD on high-resolution computed tomography of the chest, elevated serum IgG4 concentrations, and infiltration of numerous IgG4+ cells in the lungs and analysed their clinico-radiolo-histopathological findings. After expert multidisciplinary discussions, the patients were classified as definite-IgG4-RD (d-IgG4-RD) or mimickers. Thereafter, the patients were assessed according to the classification criteria. Results: Among the 28 patients included, seven were diagnosed with d-IgG4-RD, and 21 as mimickers, including 16 patients with IgG4+ IP. Five of seven patients with d-IgG4-RD were classified as IgG4-RD, while 12 of 16 patients with IgG4+ IP were excluded by the classification criteria. Conclusion: Most cases of IgG4+ IP were excluded by the classification criteria; they should be treated differently from IgG4-RD.

Kenji Tomii

Papers

Facile Discrimination of Aldose Enantiomers by Reversed-Phase HPLC

Nationwide prospective registry of idiopathic interstitial pneumonias with central multidisciplinary diagnosis in Japan (JIPS Registry): Analysis of disease progression

Respiratory lesions of IgG4-related disease classified by 2019 ACR/EULAR criteria: A retrospective study