Stereoselective synthesis and antimicrobial activity of steroidal C-20 tertiary alcohols with thiazole/pyridine side chain.

Stereoselective synthesis of novel steroidal C-20 tertiary alcohols with thiazole and pyridine side chain using Grignard reaction of steroidal ketones and thiazole/pyridine magnesium bromide have been realized. These molecules were evaluated in vitro for their antifungal and antibacterial activities. Most of the compounds exhibited significant antifungal and antibacterial activity against all the tested strains.

Synthesis and biological evaluation of bile acid dimers linked with 1,2,3-triazole and bis-beta-lactam.

We report herein the synthesis and biological evaluation of bile acid dimers linked through 1,2,3-triazole and bis-beta-lactam. The dimers were synthesized using 1,3-dipolar cycloaddition reaction of diazido bis-beta-lactams , and terminal alkynes derived from cholic acid/deoxycholic acid in the presence of Cu(i) catalyst (click chemistry). These novel molecules were evaluated in vitro for their antifungal and antibacterial activity.

Synthesis of chimeric tetrapeptide-linked cholic acid derivatives: impending synergistic agents.

Tetrapeptides derived from glycine and beta-alanine were hooked at the C-3beta position of the modified cholic acid to realize novel linear tetrapeptide-linked cholic acid derivatives. All the synthesized compounds were tested against a wide variety of microorganisms (gram-negative bacteria, gram-positive bacteria and fungi) and their cytotoxicity was evaluated against human embryonic kidney (HEK293) and human mammary adenocarcinoma (MCF-7) cell lines. While relatively inactive by themselves, these compounds interact synergistically with antibiotics such as fluconazole and erythromycin to inhibit growth of fungi and bacteria, respectively, at 1-24 microg/mL.

Synthesis and antimicrobial activity of beta-lactam-bile acid conjugates linked via triazole.

Synthesis of novel 1,2,3-triazole-linked beta-lactam-bile acid conjugates 17-24 using 1,3-dipolar cycloaddition reaction of azido beta-lactam and terminal alkyne of bile acids in the presence of Cu(I) catalyst (click chemistry) have been realized. These molecules were evaluated in vitro for their antifungal and antibacterial activities. Most of the compounds exhibited significant antifungal and moderate antibacterial activity against all the tested strains.

Steroidal conjugates and their pharmacological applications.

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.

Amino functionalized novel cholic acid derivatives induce HIV-1 replication and syncytia formation in T cells.

Synthesis of C-11 azido/amino functionalized cholic acid derivatives has been achieved in excellent yields. Contrary to the previous prediction of analogous compounds to be HIV-1 protease inhibitors, in the present study these novel cholic acid derivatives induced host cell fusion during the progress of HIV-1 infection and produced multinucleated giant cells. This is the first report of syncytia induction and enhancement of viral replication in HIV-1 infected T cells by cholic acid derivatives.

Ionic hydrogenation of C-20, 22-ketene dithioacetal: stereoselective synthesis of steroidal C (20R) aldehydes.

Homologation of 16-dehydropregnenolone acetate leads to excellent stereocontrolled synthesis of unnatural C (20R) aldehydes and through compound .

New steroidal dimers with antifungal and antiproliferative activity.

Bile acid-derived novel amphiphilic topology was designed and synthesized in the form of steroidal dimers. These dimers were tested for antifungal and antiproliferative activity in vitro. N(1),N(3)-Diethylenetriaminebis[cholic acid amide] was found to be active against C.

Bile acid amides derived from chiral amino alcohols: novel antimicrobials and antifungals.

Cholic and deoxycholic acid amides 10-17 have been synthesised from (1R,2R)-1-phenyl-2-amino-1,3-propanediol 2, (1S,2S)-1-phenyl-2-amino-1,3-propanediol 4, (1R,2R)-1-para-nitrophenyl-2-amino-1,3-propanediol 3, (1S,2S)-1-para-nitrophenyl-2-amino-1,3-propanediol 5. Amide 12 derived from N-succinimidyl ester 9 of deoxycholic acid and (1R,2R)-1-phenyl-2-amino-1,3-propanediol 2, found to be active against Cryptococcus neoformans and the amide 17 obtained from N-succinimidyl ester 9 of deoxycholic acid and (1S,2S)-1-para-nitrophenyl-2-amino-1,3-propanediol 5, is found to be potent against various gram-positive bacteria.