Guggulsterone - a potent bioactive phytosteroid: synthesis, structural modification, and its improved bioactivities

Guggulsterone is a phytosteroid derived from the oleo-gum resin of the critically endangered plant Commiphora wightii. This molecule has attracted increasing attention due to its excellent biochemistry potential and the compound has consequently been evaluated in clinical trials. With a low concentration in natural resources but wide medicinal and therapeutic value, chemists have developed several synthetic routes for guggulsterone starting from various steroid precursors. Moreover, numerous studies have attempted to modify its structure to improve the biological properties. Nowadays, green and sustainable chemistry has also attracted more attention for advanced chemical processes and reactions in steroid chemistry. The present review aimed to summarize the literature and provide an update about the improvements in the chemical synthesis and structural modification of guggulsterone from the view of green chemistry. Moreover, this review encompasses the improved activities of structurally modified guggulsterone derivatives. We expect that the information provided here will be useful to researchers working in this field and on this molecule.

Correction: Bakuchiol - a natural meroterpenoid: structure, isolation, synthesis and functionalization approaches

Correction for ‘Bakuchiol – a natural meroterpenoid: structure, isolation, synthesis and functionalization approaches’ by T. P. Adarsh Krishna et al., RSC Adv., 2022, 12, 8815–8832, DOI: 10.1039/D1RA08771A.

Bakuchiol – a natural meroterpenoid: structure, isolation, synthesis and functionalization approaches

Bakuchiol is an emblematic meroterpene class of natural product extracted from Psoralea corylifolia. It has been reported to possess a broad range of biological and pharmacological properties and is considered as a leading biomolecule. It is highly desirable to devise an efficient approach to access bakuchiol and its chemical biology applications. In this review we provided structural features, isolation methods, various chemical routes and late-stage functionalization (LSF) approaches for bakuchiol and its derivatives. Moreover, this review encompasses the structure–activity relationships (SAR), value-added contributions and future perspectives of bakuchiol

The isolation methods, various chemical routes and late-stage functionalization approaches and structure–activity relationships of bakuchiol – a meroterpene class of natural product has been discussed in detail.

Pharmaco-chemical profiling of Desmodium gangeticum (L.) DC. with special reference to soil chemistry

BACKGROUND

Desmodium gangeticum (L.) DC. (Fabaceae) (DG) is a perennial non-climbing herb or shrub and folklore medicine, widely shows a large number of medicinal properties, as well as contains divergent bioactive compounds. Many of the herbal formulations contain this medicinal plant, which is considered as master of medicinal plant in Ayurveda. This study is an attempt to establish this plant material based on its pharmaco-chemical profiles with special reference to soil chemistry. The pharmaco-chemical features such as organoleptic, DNA sequence, physicochemical, proximate, phytochemical, UV, and FTIR profiling were carried out using standard techniques. Moreover, the ADME-PK properties of the selected molecules were established.

RESULTS

The pharmaco-chemical features like organoleptic, DNA sequence, physicochemical, proximate, phytochemical, UV, and FTIR profiling, ADME-PK properties, and soil chemistry of D. gangeticum revealed its unique and diagnostic peculiarities. DNA barcoding showed that the sequence was 99.77% similar to D. gangeticum (KP094638) having 100% query coverage. The soil analysis revealed the presence of moderately high content of NPK and sufficient amount of all essential macro- and micronutrients (S, Fe, Mn, Cu, Zn, and B). The phytochemical profiling showed that the ethanolic extract of the aerial part contained glycoside, amino acid, phenols, alkaloids, flavonoids, and coumarins, while the ethanolic root extract of the plant revealed the presence of glycoside, amino acid, phenols, alkaloids, flavonoids, coumarins, and triterpenoids. FTIR results indicated that the plant extracts are mainly rich in phenolic derivatives. ADME-PK properties of pterocarpan such as gangetin (1a), gangetinin (1b), desmocarpin (1c), and desmodin (1d) were found to pass the Lipinski, Ghose, Veber, and Egan rules, supporting the drug-likeliness.

CONCLUSION

This is the first record of pharmaco-chemical profiling of D. gangeticum along with soil chemistry, and this information helps in the proper identification and future studies on this species.

GRAPHIC ABSTRACT

Oxidative radical coupling of hydroquinones and thiols using chromic acid: one-pot synthesis of quinonyl alkyl/aryl thioethers

An efficient, simple and practical protocol for one-pot sequential oxidative radical C–H/S–H cross-coupling of thiols with hydroquinones (HQs) and oxidation leading to the formation of quinonyl alkyl/aryl thioethers using H₂CrO₄ was developed. This cross-coupling of thiyl and aryl radicals offers mono thioethers in good to moderate yield and works well with a wide variety of thiols. Similarly, this method works well for coupling of 2-amino thiophenol and HQs to form phenothiazine-3-ones 5a–c. C–S bond formation via thioether synthesis was observed using a chromium reagent for the first time. Theoretical studies on the pharmacokinetic properties of compounds 5a–c revealed that due to drug-like properties, compound 5b strongly binds with Alzheimer's disease (AD) associated AChE target sites.

Oxidative radical C–H/S–H cross coupling of hydroquinones and thiols and oxidation to quinone using a H₂CrO₄ system was developed.