Two new steroidal glycosides with unique structural feature of 14α-hydroxy-5β-steroids from Reineckia carnea

Anticancer potential of cardiac glycosides and steroid-azole hybrids

Steriods are well-known scaffolds that have a widespread occurrence in different compounds characterized by extensive biological properties including anticancer activity. Structural modifications on steroids always generate potential lead compounds with superior bioactivity, and creation of steroid hybrids by combining steroid with other anticancer pharmacophores in one molecule, which can exert the anticancer activity through different mechanisms, is one of the most promising strategies to enhance efficiency, overcome drug resistance and reduce side effects. Sugars and azoles, can act on diverse receptors, proteins and enzymes in cancer cells, are pharmacologically significant scaffolds in the development of novel anticancer agents. Therefore, steroid-sugar hybrids cardiac glycosides and steroid-azole hybrids are privileged scaffolds for the discovery of novel anticancer candidates. This review emphasized on the development, the structure-activity relationship and the mechanism of action of cardiac glycosides and steroid-azole hybrids with potential application for fighting against various cancers including drug-resistant forms to facilitate further rational design of novel drug candidates covering articles published between 2015 and 2020.

Three new steroidal components from the roots of reineckia carnea

A new coprostanol glycoside, 26-trihydroxy-16, 22-dioxo-3β-[(α-L-rhamnopyranosyl)oxy]-5β-cholestan-1β-yl O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranoside (1) (25S)-5β-spirostan-1β,2β,3β, 4β,5β, 6β-hexol (2), a new C-22 steroidal lactone saponin, (20 R)-16β-trihydroxy-3β-[(α-L-rhamnopyranosyl)oxy]-1β-[(O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl)oxy]-5β-pregnane-20-oic acid γ-lactone (3) along with two known pregnane glycosides (4 and 5) were obtained from the roots of Reineckia carnea. Their structures were determined by 1 D, 2 D NMR, IR and MS data analysis. In addition, the cytotoxic activities in HT-29, HCT116, H1299 and A549 tumor cells of the isolated compounds (1 - 5) were determined by the MTT method. The results showed that only compound 1 exhibited weak effect against these cells with IC₅₀ values ranging from 63.36 μM to 105.01 μM.

A novel method for synthesis of α-spinasterol and its antibacterial activities in combination with ceftiofur

In this study, we designed a novel method of the synthesis of α-spinasterol from commercially available stigmasterol and explored the combinational effect of the α-spinasterol with ceftiofur in vitro against S. pullorum cvcc533, S. pneumoniae CAU0070, E. coli, and S. aureus. α-Spinasterol was obtained by a key reaction of Bamford-Stevens reaction with a desirable yield for five steps. The combination of α-spinasterol and ceftiofur showed stronger synergetic effect against the four pathogenic strains compared with that of stigmasterol and ceftiofur alone. In time-kill analyses, at concentrations above the MICs, ceftiofur in combination with α-spinasterol exhibited time-dependency and concentration-dependency comparing to time dependency with ceftiofur alone. We conclude that the combination usage of α-spinasterol and ceftiofur is an effective and promising strategy against the four pathogenic bacterial strains in vitro.