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Bisbibenzyls are specialized metabolites found exclusively in liverworts, until recently; they represent chemical markers of liverworts. Their occurrence in vascular plants was noticed in 2007, when they were found in Primula veris subsp. macrocalyx from Russia. This report prompted us to chemically analyze the two most common Serbian Primula species, P. veris subsp. columnae and P. acaulis, in order to determine the presence of bisbibenzyls in them. Our study revealed nine structurally distinct bisbibenzyls (1-9), identified based on 1D and 2D NMR, IR, UV and HRESIMS data. Among them were five previously undescribed compounds (2-6). The remaining compounds found and previously described in the literature were: the bisbibenzyls riccardin C (1), isoperrottetin A (7), isoplagiochin E (8) and 11-O-demethylmarchantin I (9), as well as 4-hydroxyphenylmethylketone (10) and 4-hydroxy-3-methoxyphenylmethylketone (11). Riccardin C was the most dominant bisbibenzyl in both species studied. Previously, it was the first bisbibenzyl found in vascular plants (P. veris subsp. macrocalyx). An assessment of the cytotoxic activity of the isolated compounds against A549 lung cancer and healthy MRC5 cell lines was also the subject of our study. Compounds 6 and 9 exhibited significant cytotoxic activity expressed by IC 50 values of 12 μM, but the selectivity was not satisfactory., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Appendiceal signet ring cell carcinoma (ASRCC) is a rare and aggressive form of appendiceal cancer, often presenting with nonspecific symptoms that overlap with acute appendicitis. Early diagnosis and appropriate management are crucial for improving patient outcomes in these rare malignancies. This case report and literature review aims to raise awareness among clinicians about ASRCC of the appendix as a cause of acute appendicitis and highlight the importance of considering this diagnosis in patients with atypical presentations or unexpected histopathological findings. We present a 65-year-old female patient with ASRCC who underwent successful surgical treatment and remains disease-free at the one-year follow-up. It also highlights the necessity of early detection and appropriate treatment in order to improve patient outcomes. In addition, a comprehensive literature review is provided, discussing the clinical presentation, histopathological characteristics, potential pathogenesis, treatment options, and prognosis of ASRCC.

New aurone epoxide, 2,10-oxy-10-methoxysulfuretin ( 14 ), and new auronolignan ( 15 ), named cotinignan A, were isolated by silica gel column and semipreparative HPLC chromatography from the methylene chloride/methanol extract of Cotinus coggygria Scop. heartwood. In addition, thirteen known secondary metabolites namely sulfuretin, 2,3- trans -fustin, fisetin, butin, butein, taxifolin, eriodictyol, 3',5,5',7-tetrahydroxyflavanone, 3',4',7-trihydroxyflavone, 3- O -methyl-2,3- trans -fustin, 3- O -galloyl-2,3- trans -fustin, β -resorcylic acid and 3- O - β -sitosterol glucoside were isolated as well. Their structures were elucidated by 1D and 2D NMR, HR-ESI-MS, IR and UV. Ten out of eleven isolated flavonoids possess 7, 3' and 4' hydroxy groups. These structural features could be considered as chemotaxonomic characteristic of flavonoids from C. coggygria . Cotinignan A ( 15 ) represents new subclass of secondary metabolites - auronolignans.

Seven new bisbibenzyls (1-7) were isolated from the methanol extract of the liverwort Lunularia cruciata along with one previously known bibenzyl and five known bisbibenzyls. The structures of compounds 1-7 were elucidated on the basis of the spectroscopic data. These newly isolated bisbibenzyls may be divided into two groups, the acyclic bisbibenzyls, perrottetins (1-3), and the cyclic analogues, riccardins (4-7). Besides standard perrottetin and riccardin structures (1 and 4, respectively), they contain phenanthrene (3 and 5), dihydrophenanthrene (2), and quinone moieties (6 and 7), rarely found in natural products. The new compounds 3 and 5, as well as the known riccardin G, exhibited cytotoxic activity against the A549 lung cancer cell line with IC 50 values of 5.0, 5.0, and 2.5 μM, respectively.

Hexane extracts of Heracleum verticillatum, H. sibiricum, H. angustisectum, and H. ternatum were studied for their furanocoumarin content antioxidant potential and acetylcholinesterase and α-amylase inhibitory activities. Quantification of the furanocoumarins was performed by 1 H-NMR. Pimpinellin was found to be the main component in the roots of all studied species. Bergapten and imperatorin were the major compounds in the fruits of H. sibiricum and H. verticillatum, respectively, while byakangelicol dominated in H. angustisectum and H. ternatum fruits. The leaf and fruit extracts of H. angustisectum demonstrated the highest DPPH radical scavenging activity and TEAC (IC 50 0.58 mg/mL and 1.83 mm, respectively). The root extracts of H. verticillatum and H. angustisectum were found to be the most effective against acetylcholinesterase (IC 50 0.30 and 0.34 mg/mL, respectively). The studied extracts were not active or demonstrated a weak inhibitory effect (%Inh. up to 29.7) towards α-amylase., (© 2019 Wiley-VHCA AG, Zurich, Switzerland.)

The NMR-observable nuclei of the acidic and basic compounds experience pH dependence in chemical shift. This phenomenon can be exploited in NMR titrations to determine p K a values of compounds, or in pH measurement of solutions using dedicated pH reference compounds. On the other hand, this sensitivity can also cause problems in, for example, metabolomics, where slight changes in pH result in significant difficulties for peak alignment between spectra of set of samples for comparative analysis. In worst case, the pH sensitivity of chemical shifts can prevent unambiguous identification of compounds. Here, we propose an alternative approach for NMR identification of pH-sensitive analytes. The 1 H and X ( 13 C, 15 N, 31 P, ...) chemical shifts in close proximity to the acidic or basic functional group should, when presented as ordered pairs, express piecewise linear correlation with distinct slope, intercept, and range. We have studied the pH dependence of 1 H and 31 P chemical shifts of the CH 3 -P moiety in urinary metabolites of nerve agents sarin, soman and VX using 2D 1 H- 31 P fast-HMQC spectroscopy. The 1 H and 31 P chemical shifts of these chemicals appear in very narrow range, and due to subtle changes in sample pH the identification on either 1 H or 31 P chemical shift alone is uncertain. However, if the observed 1 H and 31 P chemical shifts of the CH 3 -P moiety of individual compounds are presented as ordered pairs, they fall into distinct linear spaces, thus, facilitating identification with high confidence.