Glycosidic bonds attached to each and every other (1 4)– each 2)–D-xylopyranosyl]-16-acetoxy-9-H-lanosta-7,24attached to each and every other by attached to D-quinovopyranosyl-(1 along with the activity ofH , and 1) with pentasaccharide mono -(12)-glycosidicother by , bonds cucumariosides H5 (3) and (four) (Figure the activity of -(12)-glycosidic bonds diene-18,20-diol. mp 23840 C, 20 chains  cucumariosides H5 (3) and H (four) (Figure 1) withH5 (3) and H (4) (Figure 1) with pentasaccharide HR MALDI TOF MS m/z: cucumariosides pentasaccharide monosulfated (c 0.1, C5 H5 N), monosulfated chains D 1125.5812 (calc 1125.5816) [M Na] .Mar. Drugs 2021, 19,19 of4. ML-SA1 Agonist Conclusions The SAR for the sea cucumber triterpene glycosides illustrated by their action on mouse erythrocytes, is quite difficult. Nonetheless, in our study, a number of clear trends were found, supplying substantial membranolytic activity for the glycosides, namely: the presence of a developed carbohydrate chain PF-06873600 Formula composed of 4 to six monosaccharide residues (with linear tetrasaccharide fragment) or a disaccharide chain having a sulfate group; the availability of 18(20)- or 18(16)-lactone and a standard (non-shortened) side chain; the presence of 9-H, 7(8)-ene fragment or 9(11)-double bond. It was also observed that the influence of sulfate groups on the membranotropic action from the glycosides depends on the architecture on the sugar chain and the positions of sulfate groups. Hydroxyl groups attached to unique positions of aglycone side chains incredibly reduce the activity. Using an in silico method of full-atom MD simulations for the investigation of interactions of sea cucumber triterpene glycosides using the molecules composing the model lipid bilayer membrane has resulted in the clarification of numerous traits from the molecular mechanisms of membranolytic action of these compounds. It was revealed that the studied glycosides bound to the membrane surface mostly by hydrophobic interactions and hydrogen bonds, but the mode of such interactions depended around the aglycone side chain structure and varied to an awesome extent. The formation of multimolecular lipid/glycoside complexes led to membrane curvature followed by the subsequent membranolytic effects from the glycosides. Distinctive mechanisms of glycoside/membrane interactions were found for cucumariosides A1 (40), A8 (44), and A2 (59). The first mechanism, inherent for 40 and 44, was realized by means of the pore’s formation differed by the shape, stoichiometry, and also the impact of diverse noncovalent interactions into complex assembling, based on the glycoside structural peculiarities. The second mode of membranotropic action was realized by 59 via the formation of phospholipid and cholesterol clusters inside the outer and inner membrane leaflets, correspondingly. The observed peculiarities of membranotropic action are in great agreement together with the corresponding information of in vitro hemolytic activity with the investigated compounds [28,29]. In fact, the hemolytic activity of pore-forming cucumariosides A1 (40) and A8 (44) were 0.07 and 0.70 /mL, correspondingly. The value for cluster-forming cucumarioside A2 (59) was four.70 /mL, and cucumarioside A7 (45) demonstrating the weakest capacity to embed the membrane, was not active for the maximal studied concentration of 100.0 /mL. Further in silico studies on the relationships of your membrane lipid composition and structural peculiarities from the glycosides demonstrating membranolytic activity.