Steroidal Conjugates and Their Pharmacological Applications

Abstract

Nature continues to be the main source of inspiration for synthetic chemists in their quest to make novel conjugates, which can have different physical, biological and medicinal properties. Nature makes these conjugates from mixed biosynthesis and some of these chimeras are found to exhibit unusual biological properties. During the past two decades design of such entities has been receiving increasing attention. Among the hybrid natural products, hybrids of steroid frameworks have attracted great attention due to the significant biological properties and numerous therapeutic effects of steroids. The developments made over the past few years in the isolation, design and synthesis of steroidal conjugates and their pharmacological applications are discussed in this review.

Synthesis, Spectroscopic and Semiempirical Studies of New Quaternary Alkylammonium Conjugates of Sterols

“…Additionally, analyses of the biological prediction activity spectra for the new esters prepared herein are good examples of in silico studies of chemical compounds. (1) or (2) (11), (15) n = 6 (8), (12), (16) n = 8 (9), (13), (17) n = 10 (10), (14), (18) …”

“…Connecting steroid compound molecules with natural products such as pyrimidines, purines, alkaloids or polyamines allows one to obtain new compounds with high biological activity as well as complexing or gelator agents. All compounds of this type may be classified as steroid conjugates [14].…”

Quaternary Alkylammonium Conjugates of Steroids: Synthesis, Molecular Structure, and Biological Studies

“…The basic criteria for the synthesis of biologically active conjugates of steroids and polyamines have been given by Salunke et al [11]. Firstly, the structure must have a rigid extensive hydrophobic part and a flexible hydrophilic chain with a polar head group attached to a hydrophobic part.…”

“…The best-known compound of this type is squalamine (3β-spermidine-7α-hydroxy-5α-cholestan-24R-yl sulphate) (1) (Figure 1). The steroid-polyamine conjugate was isolated from the liver tissues of the dogfish shark (Squalus acanthias) [11][12][13][14]. This aminosterol is a novel broad-spectrum antibiotic and exhibits a biocidal activity against Gram-positive and Gram-negative bacteria, fungi, protozoa, and viruses [15][16][17][18][19][20][21][22][23].…”

Recent Developments in the Isolation and Synthesis of D‐Homosteroids and Related Compounds

“…Mehta et al 3 and Tietze et al 4 have reported numerous examples of the synthesis of natural products, including steroids, where this concept for the synthesis of new derivatives was utilized. Steroidal conjugates and their pharmacological applications have been discussed by Salunke et al 5 and the use of bile acids as building blocks of supramolecular hosts has been surveyed by Tamminen and Kolehmainen. 6 Another possible way to obtain new, useful steroids for medicinal chemical purposes is to modify the original sterane skeleton, for example by the enlargement of ring D. The insertion of one additional carbon atom in ring D may alter the biological properties.…”