Steroids Bearing Heteroatom as Potential Drugs for Medicine

Expanding Diversity of Fused Steroid-Quinoline Hybrids by Sequential Amination/Annulation/Aromatization Reactions

Viable alternative approaches to a variety of ring A and ring D-fused steroid-quinoline hybrids, along with ring A, D-fused, and/or ring A-fused, side chain-substituted steroid-bis-quinolines were explored by means of sequential amination/annulation/aromatization reactions of suitable ketosteroids with 2-acyl-substituted anilines. Key factors directing the chemoselective behavior of polyfunctionalized substrates were investigated. Remarkably, the use of TMSOTf as an alternative promoter/catalyst enabled the direct synthesis of the desired hybrids, avoiding the protection/deprotection steps of the conventional procedures when the starting substrates contained labile functional groups.

Solid-State NMR-Assisted Dynamic Characterization of two Isostructural Solvates of 5α-Bromo-6β,19-Epoxy-Androstan-3β,17β-Diol Diacetate

The study reports on the rotational dynamics of acetone-d6 (Form II) and DMSO-d6 (Form III) within the crystalline structures of two solvates of 5α-bromo-6β,19-epoxy-androstan-3β,17β-diol diacetate (Compound 1) by means of solid-state Nuclear Magnetic Resonance through the quadrupolar 2H spin-echo technique. The spectral data allowed the determination of the activation barriers (Ea) for rotation of the solvent molecules, with 6.24 kcal mol-1 for deuterated acetone in the Form II-d6 and 8.19 kcal mol-1 for the case of deuterated dimethylsulfoxide in Form III-d6. The use of calculations and the Transition State theory through the linear Eyring equation suggested that although the acetone molecules experience a low activation energy (Ea = 6.24 kcal mol-1), a highly ordered transition state during the molecular motion reduces its rotational rate. Conversely, the DMSO molecules, with a higher activation barrier (Ea = 8.19 kcal mol-1) attributed to a denser packing coefficient, have faster motional rates. Based on complementary X-ray and NMR spectroscopy techniques, this work provides detailed insights into the mechanistic phenomena involved in the mobility of small molecules inside crystalline arrangements.

Concise Synthesis of Naphthalene-Based 14-Aza-12-Oxasteroids

A concise, transition metal-free four-step synthetic pathway has been developed for the synthesis of tetracyclic heterosteroidal compounds, 14-aza-12-oxasteroids, starting from readily available 2-naphthol analogues. After conversion of 2-naphthols to 2-naphthylamines by the Bucherer reaction, subsequent selective C-acetylation was achieved via the Sugasawa reaction and reduction of the acetyl group using borohydride, which resulted into the corresponding amino-alcohols. The naphthalene-based amino-alcohols underwent double dehydrations and double intramolecular cyclization with oxo-acids leading to one-pot formation of a C-N bond, a C-O bond and an amide bond in tandem, to generate two additional rings completing the steroidal framework. A series of 14-aza-12-oxasteroids were synthesized using our developed synthetic strategy in moderate yields, and the structure of one of the final products, 12a-Methyl-11-phenyl-11,12a-dihydro-1H-naphtho[2,1-d]pyrrolo[2,1-b][1,3]oxazin-3(2H)-one, was further confirmed by single crystal X-ray crystallography.

Dichroa febrifuga Lour.: A review of its botany, traditional use, phytochemistry, pharmacological activities, toxicology, and progress in reducing toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Dichroa febrifuga Lour., a toxic but extensively used traditional Chinese medicine with a remarkable effect, is commonly called "Changshan" in China. It has been used to treat malaria and many other parasitic diseases.

AIM OF THE REVIEW

The study aims to provide a current overview of the progress in the research on traditional use, phytochemistry, pharmacological activities, toxicology, and methods of toxicity reduction of D. febrifuga. Additionally, further research directions and development prospects for the plant were put forward.

MATERIALS AND METHODS

The article uses "Dichroa febrifuga Lour." "D. febrifuga" as the keyword and all relevant information on D. febrifuga was collected from electronic searches (Elsevier, PubMed, ACS, CNKI, Google Scholar, and Baidu Scholar), doctoral and master's dissertations and classic books about Chinese herbs.

RESULTS

30 chemical compounds, including alkaloids, terpenoids, flavonoids and other kinds, were isolated and identified from D. febrifuga. Modern pharmacological studies have shown that these components have a variety of pharmacological activities, including anti-malarial activities, anti-inflammatory activities, anti-tumor activities, anti-parasitic activities and anti-oomycete activities. Meanwhile, alkaloids, as the material basis of its efficacy, are also the source of its toxicity. It can cause multiple organ damage, including liver, kidney and heart, and cause adverse reactions such as nausea and vomiting, abdominal pain and diarrhea. In the current study, the toxicity can be reduced by modifying the structure of the compound, processing and changing the dosage forms.

CONCLUSIONS

There are few studies on the chemical constituents of D. febrifuga, so the components and their structure characterization contained in it can become the focus of future research. In view of the toxicity of D. febrifuga, there are many methods to reduce it, but the safety and rationality of these methods need further study.

Naturally Occurring Norsteroids and Their Design and Pharmaceutical Application

The main focus of this review is to introduce readers to the fascinating class of lipid molecules known as norsteroids, exploring their distribution across various biotopes and their biological activities. The review provides an in-depth analysis of various modified steroids, including A, B, C, and D-norsteroids, each characterized by distinct structural alterations. These modifications, which range from the removal of specific methyl groups to changes in the steroid core, result in unique molecular architectures that significantly impact their biological activity and therapeutic potential. The discussion on A, B, C, and D-norsteroids sheds light on their unique configurations and how these structural modifications influence their pharmacological properties. The review also presents examples from natural sources that produce a diverse array of steroids with distinct structures, including the aforementioned A, B, C, and D-nor variants. These compounds are sourced from marine organisms like sponges, soft corals, and starfish, as well as terrestrial entities such as plants, fungi, and bacteria. The exploration of these steroids encompasses their biosynthesis, ecological significance, and potential medical applications, highlighting a crucial area of interest in pharmacology and natural product chemistry. The review emphasizes the importance of researching these steroids for drug development, particularly in addressing diseases where conventional medications are inadequate or for conditions lacking sufficient therapeutic options. Examples of norsteroid synthesis are provided to illustrate the practical applications of this research.