6-(4'-Aryl-1',2',3'-triazolyl)-spirostan-3,5-diols and 6-(4'-Aryl-1',2',3'-triazolyl)-7-hydroxyspirosta-1,4-dien-3-ones: Synthesis and analysis of their cytotoxicity

Plant based steroidal and triterpenoid sapogenins: Chemistry on diosgenin and biological aspects

Plants are rich in steroidal and triterpenoid saponins. Diosgenin is an important sapogenin obtained from various steroidal saponins and specially from dioscin. It possesses diverse pharmacological activities as it is capable of modulating various endogenous pathways. Diosgenin is the molecule of choice for the industrial synthesis of the steroid based clinical drugs namely progesterone, testosterone, dexamethasone, dehydroepiandrosterone, vitamin D3, steroidal contraceptive pills, norethindrone, norgestrel etc. Diosgenin has been a molecule of discussion due to its high demand in industry as well as for future research applications. Present review describes its chemistry and detailed pharmacological profile.

The Pros and Cons of Estrogens in Prostate Cancer: An Update with a Focus on Phytoestrogens

The role of estrogens in prostate cancer (PCa) is shrouded in mystery, with its actions going from angelic to devilish. The findings by Huggins and Hodges establishing PCa as a hormone-sensitive cancer have provided the basis for using estrogens in therapy. However, despite the clinical efficacy in suppressing tumor growth and the panoply of experimental evidence describing its anticarcinogenic effects, estrogens were abolished from PCa treatment because of the adverse secondary effects. Notwithstanding, research work over the years has continued investigating the effects of estrogens, reporting their pros and cons in prostate carcinogenesis. In contrast with the beneficial therapeutic effects, many reports have implicated estrogens in the disruption of prostate cell fate and tissue homeostasis. On the other hand, epidemiological data demonstrating the lower incidence of PCa in Eastern countries associated with a higher consumption of phytoestrogens support the beneficial role of estrogens in counteracting cancer development. Many studies have investigated the effects of phytoestrogens and the underlying mechanisms of action, which may contribute to developing safe estrogen-based anti-PCa therapies. This review compiles the existing data on the anti- and protumorigenic actions of estrogens and summarizes the anticancer effects of several phytoestrogens, highlighting their promising features in PCa treatment.

Steroid-triazole conjugates: A brief overview of synthesis and their application as anticancer agents

Steroids are biomolecules that play pivotal roles in various physiological and drug discovery processes. Abundant research has been fuelled towards steroid-heterocycles conjugates over the last few decades as potential therapeutic agents against various diseases especially as anticancer agents. In this context various steroid-triazole conjugates have been synthesized and studied for their anticancer potential against various cancer cell lines. A thorough search of the literatures revealed that a concise review pertaining the present topic is not compiled. Therefore, in thus review we summarize the synthesis, anticancer activity against various cancer cell lines and structure activity relationship (SAR) of various steroid-triazole conjugates. This review can lay down the path towards the development of various steroid-heterocycles conjugates with lesser side effects and profound efficacy.

Synthesis of fully functionalized spirostanic 1,2,3-triazoles by the three component reaction of diosgenin azides with acetophenones and aryl aldehydes and their biological evaluation as antiproliferative agents

Diosgenin is of significant interest due to its biological activity and synthetic application. In this study, we report the synthesis of a series of spirostanic 1,4,5-trisubstituted 1,2,3-triazoles by the three component reaction of (25R)-6-azidospirostan-3,5-diols with acetophenones and aryl aldehydes. The one-pot two step synthesis proceeds through the in situ formation of (E)-chalcones and copper catalyzed reaction with organic azides in DMF medium. Structural diversity was achieved by varying the aldehyde and acetophenone nature as well as the spirostanic azide stereochemistry. The results of in vitro biological assays showed that fully decorated spirostanic 1,2,3-triazoles exerted significant and selective antiproliferative activity against MCF-7, glioblastoma (SNB-19, T98G, A-172) and neuroblastoma (IMR-32, SH-SYSY) (HCT116) cell lines (GI₅₀ in the single-digit micromolar range). The data revealed that benzoyl and aryl substitutions in the triazole ring introduced at the 6β-position significantly improved the anti-tumor activity of (25R)-6-azidospirostan-3β,5α-diols. This position on the spirostan core may be the favourable to synthesize of potent anticancer leads from diosgenin.

Therapeutic potential of 1,2,3-triazole hybrids for leukemia treatment

Leukemia, a hematological malignancy originating from the bone marrow, is the principal cancer of childhood. In recent decades, improved remission rates and survival of patients with leukemia have been achieved due to significant breakthroughs in the treatment. However, chemoresistance and relapse are common, creating an urgent need for the search for novel pharmaceutical interventions. 1,2,3-Triazole is one of the most fascinating pharmacophores in the discovery of new drugs, and several 1,2,3-triazole derivatives have already been used in clinics or are under clinical evaluation for the treatment of cancers. In particular, 1,2,3-triazole hybrids could suppress tumor proliferation, invasion, and metastasis by inhibiting enzymes, proteins, and receptors in cancer cells, revealing their potential as putative antileukemic agents. This review covers the recent advances regarding the 1,2,3-triazole hybrids with potential antileukemic activity, focusing on the chemical structures, structure-activity relationship, and mechanisms of action, covering articles published from January 2017 to January 2022.

1,2,3-Triazole derivatives with anti-breast cancer potential

Abstract:

Breast cancer is one of the most prevalent malignant diseases and one of the main mortality causes among women across the world. Despite advances in chemotherapy, drug resistance remains major clinical concerns, creating an urgent need to explore novel anti-breast cancer drugs. 1,2,3-Triazole is a privileged moiety, and its derivatives could inhibit cancer cell proliferation, and induce the cell cycle arrest and apoptosis. Accordingly, 1,2,3-triazole derivatives possess profound activity against various cancers including breast cancer. This review summarizes the latest progresses related to the anti-breast cancer potential of 1,2,3-triazole derivatives, covering articles published from January 2017 to December 2021. The mechanisms of action and structure-activity relationships (SARs) are also discussed for further rational design of more effective candidates.

Recent advances in chemical synthesis, biocatalysis, and biological evaluation of diosgenin derivatives - A review

Extracting organic compounds from plants and developing derivatives are essential methods for drug discovery. Diosgenin, extracted from Dioscoreaceae plants, is a type of spirostan steroid with various biological effects, including anti-inflammation, neuro-protection, and apoptosis-induction. Many researchers committed their work to the chemical semi-synthesis of diosgenin derivatives to improve diosgenin's therapeutic bioavailability and expand its range of applications in disease treatment and prevention. Biotransformation, a mild whole-cell biocatalysis method, also made crucial contributions to the structural diversity of diosgenin analogs in recent years. Although the structural modification of diosgenin has made significant progress, it lacks a comprehensive review. Here, we review the chemical modification and biotransformation of diosgenin along with the biological evaluation of diosgenin derivatives to provide a reference for the structural modification strategy and pharmaceutical application of diosgenin derivatives.

Developments in the Antitumor Activity, Mechanisms of Action, Structural Modifications, and Structure-Activity Relationships of Steroidal Saponins

Steroidal saponins, a class of natural products formed by the combination of spirosteranes with sugars, are widely distributed in plants and have various biological activities, such as anti-tumor, anti-inflammatory, anti-bacterial, anti-Alzheimer's, anti-oxidation, etc. Particularly, extensive researches on the antitumor property of steroidal saponins have been received. Steroidal sapogenins, the aglycones of steroidal saponins, also have attracted much attention due to a vast range of pharmacological activities similar to steroidal saponins. In the past few years, structural modifications on the aglycones and sugar chains of steroidal saponins have been carried out and some achievements have been made. In this mini-review, the antitumor activity, action mechanisms, and structural modifications along with the structure-activity relationships of steroidal saponins and their derivatives are summarized.

Synthesis of Anti-Inflammatory Spirostene-Pyrazole Conjugates by a Consecutive Multicomponent Reaction of Diosgenin with Oxalyl Chloride, Arylalkynes and Hydrazines or Hydrazones

Steroid sapogenin diosgenin is of significant interest due to its biological activity and synthetic application. A consecutive one-pot reaction of diosgenin, oxalyl chloride, arylacetylenes, and phenylhydrazine give rise to steroidal 1,3,5-trisubstituted pyrazoles (isolated yield 46–60%) when the Stephens–Castro reaction and heterocyclization steps were carried out by heating in benzene. When the cyclization step of alkyndione with phenylhydrazine was performed in 2-methoxyethanol at room temperature, steroidal α,β-alkynyl (E)- and (Z)-hydrazones were isolated along with 1,3,5-trisubstituted pyrazole and the isomeric 2,3,5-trisubstituted pyrazole. The consecutive reaction of diosgenin, oxalyl chloride, phenylacetylene and benzoic acid hydrazides efficiently forms steroidal 1-benzoyl-5-hydroxy-3-phenylpyrazolines. The structure of new compounds was unambiguously corroborated by comprehensive NMR spectroscopy, mass-spectrometry, and X-ray structure analyses. Performing the heterocyclization step of ynedione with hydrazine monohydrate in 2-methoxyethanol allowed the synthesis of 5-phenyl substituted steroidal pyrazole, which was found to exhibit high anti-inflammatory activity, comparable to that of diclofenac sodium, a commercial pain reliever. It was shown by molecular docking that the new derivatives are incorporated into the binding site of the protein Keap1 Kelch-domain by their alkynylhydrazone or pyrazole substituent with the formation of more non-covalent bonds and have higher affinity than the initial spirostene core.

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.

Diosgenin, a steroidal saponin, and its analogs: Effective therapies against different chronic diseases

BACKGROUND

Chronic diseases are a major cause of mortality worldwide, and despite the recent development in treatment modalities, synthetic drugs have continued to show toxic side effects and development of chemoresistance, thereby limiting their application. The use of phytochemicals has gained attention as they show minimal side effects. Diosgenin is one such phytochemical which has gained importance for its efficacy against the life-threatening diseases, such as cardiovascular diseases, cancer, nervous system disorders, asthma, arthritis, diabetes, and many more.

AIM

To evaluate the literature available on the potential of diosgenin and its analogs in modulating different molecular targets leading to the prevention and treatment of chronic diseases.

METHOD

A detailed literature search has been carried out on PubMed for gathering information related to the sources, biosynthesis, physicochemical properties, biological activities, pharmacokinetics, bioavailability and toxicity of diosgenin and its analogs.

KEY FINDINGS

The literature search resulted in many in vitro, in vivo and clinical trials that reported the efficacy of diosgenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK, etc., which play a crucial role in the development of most of the diseases. Reports have also revealed the safety of the compound and the adaptation of nanotechnological approaches for enhancing its bioavailability and pharmacokinetic properties.

SIGNIFICANCE

Thus, the review summarizes the efficacy of diosgenin and its analogs for developing as a potent drug against several chronic diseases.

1-Hydroxyanthraquinones Containing Aryl Substituents as Potent and Selective Anticancer Agents

A series of 1,2-, 1,4-disubstituted or 1,2,4-trisubstituted anthraquinone-based compounds was designed, synthesized, characterized and biologically evaluated for anticancer efficacy. 2- or 4-arylated 1-hydroxy-9,10-antraquinones (anthracene-9,10-diones) were prepared by Suzuki–Miyaura cross-coupling reaction of 1-hydroxy-2-bromoanthraquinone, 1-hydroxy-4-iodoanthraquinone or 1-hydroxy-2,4-dibromoanthraquinone with arylboronic acids. The cross-coupling reaction of 2,4-dibromo-9,10-anthraquinone with arylboronic acids provide a convenient approach to 2,4-bis arylated 1-hydroxyanthraquinones with a variety of aryl substituent in the 2 and 4 position. The cytotoxicity of new anthraquinone derivatives was evaluated using the conventional MTT assays. The data revealed that six of the aryl substituted compounds among the entire series 3, 15, 16, 25, 27, 28 were comparable potent with the commercially available reference drug doxorubicin on the human glioblastoma cells SNB-19, prostate cancer DU-145 or breast cancer cells MDA-MB-231 and were relatively safe towards human telomerase (h-TERT)immortalized lung fibroblasts cells. The results suggested that the in vitro antitumor activity of synthesized 2-aryl, 4-aryl- and 2,4-diaryl substituted 1-hydroxyanthraquinones depends on the nature of the substituent within the cyclic backbone. Docking interaction of 2-, 4-substituted and 2,4-disubstituted 1-hydroxyanthraquinones indicates intercalative mode of binding of compounds with DNA topoisomerase. The interaction with the DNA of 4-aryl-13, 15, 16 and 4-(furan-3-yl)-23 1-hydroxyanthraquinones was experimentally confirmed through a change in electroforetic mobility. Further experiments with 1-hydroxy-4-phenyl-anthraquinone 13 demonstrated that the compound induced cell cycle arrest at sub-G1 phase in DU-145 cells in the concentration 1.1 μM, which is probably achieved by inducing apoptosis. 4-Arylsubstituted 1-hydroxyanthraquinones 13 and 16 induced the enhancement of DNA synthesis on SNB19 cell lines.

Stereoselective Synthesis of (-)-Verazine and Congeners via a Cascade Ring-Switching Process of Furostan-26-acid

An efficient synthetic strategy for three natural seco-type cholestane alkaloids isolated from the Veratrum plants, based on commercially available naturally occurring and abundant (-)-diosgenin (1), as exemplified in the concise asymmetric synthesis of (-)-verazine (4), (-)-veramiline (5) (proposed structure), and its 22-epimer, (-)-oblonginine (6), is presented. This work highlights the application of a cascade ring-switching process of (-)-diosgenin to achieve the E-ring opening and construction of chiral six-membered lactone challenges in seco-type cholestane alkaloid synthesis. This approach enables the synthesis of related natural and nature-like novel cholestane alkaloids, opening up opportunities for more extensive exploration of cholestane alkaloid biology.