1. Calysolins V-IX, resin glycosides from Calystegia soldanella and their antiviral activity toward herpes
Masateru Ono, et al. Chem Pharm Bull (Tokyo). 2014;62(1):97-105. doi: 10.1248/cpb.c13-00610.
Five new resin glycosides having macrolactone structures (jalapins), named calysolins V-IX (1-5), were isolated from the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae). Their structures were determined on the basis of spectroscopic data as well as chemical evidence. The isolated compounds could be classified into two macrolactone types-one having a 22-membered ring (1-4) and the other with a 27-membered ring (5). The sugar moieties of 1-5 were found to exist in partially acylated forms comprising 2S-methylbutyric acid and tiglic acid. Compounds 4 and 5 are the first representatives of the calysolic acid C as the component glycosidic acid. Additionally, the antiviral activity of 1-5, together with calysolins I-IV and soldanelline B, which are previously isolated jalapins from this plant, toward herpes simplex virus type 1 was evaluated. All the compounds showed antiviral activity.
2. Total Syntheses of Resin Glycosides Murucoidins IV and V
Jing Fang, Jing Zeng, Jiuchang Sun, Shuxin Zhang, Xiong Xiao, Zimin Lu, Lingkui Meng, Qian Wan Org Lett. 2019 Aug 16;21(16):6213-6216. doi: 10.1021/acs.orglett.9b02004. Epub 2019 Jun 24.
Murucoidins IV and V, two bioactive resin glycosides with complex yet similar structures isolated from the morning glory family, were synthesized in a convergent manner. All of the glycosylations in these syntheses including the key [3 + 2] coupling were achieved by our recently developed interrupted Pummerer reaction mediated (IPRm) glycosylations. The broad functional group compatibility of IPRm glycosylation allowed us to employ a latent-active concept and a single-pot transient protection-glycosylation-deprotection strategy which significantly improved the global synthetic efficiency.
3. Resin modified glass ionomer cements. In vitro microleakage in direct class V and class II sandwich restorations
L Sjödin, M Uusitalo, J van Dijken Swed Dent J. 1996;20(3):77-86.
Microleakage of conventional chemically cured and resin modified glass ionomer cements (GIC), a compomer and a composite resin was studied in vitro in direct class V and class II GIC/composite sandwich fillings. None of the restorative techniques investigated completely resisted microleakage at both the occlusal and gingival margins. The dentinal gingival margins exhibited the highest leakage pattern. The compomer and the resin modified GIC showed a better seal than the chemically cured GIC's. The use of a liner as separating agent between composite resin and GIC in the class II sandwich fillings did not improve the seal. The results suggest that the initial bond obtained immediately after light curing of the resin modified GIC's is stronger than that for chemically cured GIC's. The contradictory results of dye leakage studies reported in the literature are discussed and in vivo evaluations are suggested necessary to predict clinical performance.
