For 1.Figure 2. Essential HMBC and COSY correlations of 1 and 15.Mar. Drugs 2022, 20,5 ofFigure 3. Important NOEFigure three. Essential NOE correlations of 1 and 145. correlations of 1 and 145.Figure four. ECD spectra of compounds (A), and 3 (B), 14 and 15 (C) in CH3OH. Figure four. ECD spectra of compounds 11(A), 22 and 3 (B), 14 and 15 (C) in CH3 OH.Hemiacetalmeroterpenoid B (2) was isolated as a white powder and had a molecular formula of C26H36O6, determined by HRESIMS information m/z 445.25772 [M+H]+ (calcd. 445.25847) with nine degrees of unsaturation. The 1H NMR spectrum of two displayed the signal for one particular olefinic proton (H 5.42), one methoxyl (H three.56), two methines (H 1.33 and 1.89), four methylenes (H 1.12, 1.33, 1.55, 1.75, two.07, 2.12, 2.19 and two.76) and six methyls (H 1.01, 1.04, 1.18, 1.19, 1.57 and 1.82). The 13C NMR information revealed 26 carbon resonances,Mar. Drugs 2022, 20,5 ofHemiacetalmeroterpenoid B (2) was isolated as a white powder and had a molecular formula of C26 H36 O6 , determined by HRESIMS data m/z 445.25772 [M+H]+ (calcd. 445.25847) with nine degrees of unsaturation. The 1 H NMR spectrum of two displayed the signal for a single olefinic proton (H 5.42), one particular methoxyl (H 3.56), two methines (H 1.33 and 1.89), four methylenes (H 1.12, 1.33, 1.55, 1.75, two.07, 2.12, two.19 and 2.76) and six methyls (H 1.01, 1.04, 1.18, 1.19, 1.57 and 1.82). The 13 C NMR data revealed 26 carbon resonances, involving four olefinic carbons for two double bonds (C 113.five, 124.two, 137.7, 190.7), two carbonyl carbons for a single ketone (C 201.four), 1 ester carbonyl (C 172.six) (Table 1). In accordance with 1D NMR and 2D NMR information, the planar structure of 2 was comparable towards the co-isolated andrastin B (13). The apparent difference is the fact that the acetyl group at the C-3 position of compound 2 disappears. Meanwhile, the HMBC from H2 -21 to C-3 (C 99.five) also indicated that a new 6-membered ring was formed between C-1, C-2, C-3, C-10 and C-21 (Figure two). The NOESY spectrum indicated that H1 -5, H1 -9 and H3 -22 had been on the same side primarily based on the correlations of H1 -5 with H1 -9 and H3 -22. On the contrary, it was suggested that H3 -19, H3 -21, H3 -23, H3 -24, and H3 -26 have been on the other side based on the NOESY correlations of H2 -21 with H3 -23 and H3 -24, together with H3 -19 with H3 -24 and H3 -26 (Figure 3). Hence, the relative configuration of two was determined to become 3R, 5S, 8S, 9R, 10S, 13R and 14R. The absolute configuration from the stereogenic centers in two was assigned as 3R, 5S, 8S, 9R, 10S, 13R and 14R by comparing its experimental ECD spectrum with that of the calculated model molecule (Figure 4). Hemiacetalmeroterpenoid C (three) was also purified as a white powder. The molecular formula was specified as C28 H38 O7 (ten degrees of unsaturation) by HRESIMS (m/z 509.ACOT13 Protein MedChemExpress 25015 [M+Na]+ ), which can be 42 mass units higher than that of two (Figure S17).FGFR-3 Protein Formulation Analysis of its NMR information (Table 1) revealed the presence of your identical partial structure as that identified in compound two.PMID:23912708 The only difference was three has an added acetyl fragment. Finally, a weak HMBC correlation from Ac-CH3 to C-15 recommended that the acetyl fragment was attached to C-15 (Figure 2). Because compound three has the same chiral center as two, the NOESY correlation and experimental ECD spectrum of compound 3 had been in agreement with those of 2 (Figures 3 and 4). As a result, the absolute configuration of three was identified as 3R, 5S, 8S, 9R, 10S, 13R and 14R. Compound 14 was obtained as a yellow powder. Evaluation of its 1 H NMR and 13 C NMR data showed that the planar structure of.