Application of iron carbonyl complexation to the selective total synthesis of sanshools

Corey-Fuchs reaction enabled synthesis of natural products: a review

Natural products can be derived from a vast array of animals, plants and microorganisms and are generally characterized by a wide spectrum of bioactive properties such as anti-viral, anti-cancer, anti-inflammatory and anti-bacterial properties. Synthesis of natural products is of paramount importance in various fields including medicine, biotechnology and agriculture. The Corey-Fuchs reaction, also known as the Ramirez Corey-Fuchs reaction, is a pivotal organic transformation and plays a significant role in the synthesis of intricate natural products and their analogues. This review article highlights the development of the Corey-Fuchs reaction in recent years towards the synthesis of complex natural products including polyketides, alkaloids, terpenoids and peptides.

A Mini Review on Natural Safeners: Chemistry, Uses, Modes of Action, and Limitations

Herbicide injury is a common problem during the application of herbicides in practice. However, applying herbicide safeners can avoid herbicide damage. Safeners selectively protect crops against herbicide injury without affecting the biological activity of herbicides against the target weeds. However, after long-term application, commercial safeners were found to pose risks to the agricultural ecological environment. Natural safeners are endogenous compounds from animals, plants, and microbes, with unique structures and are relatively environment-friendly, and thus can address the potential risks of commercial safeners. This paper summarizes the current progress of the discovery methods, structures, uses, and modes of action of natural safeners. This study also concludes the limitations of natural safeners and prospects the future research directions, offering guidance for the practical application of natural safeners to prevent herbicide injury. This study will also guide the research and development of corresponding products.

Composition, structure and flavor mechanism of numbing substances in Chinese prickly ash in the genus Zanthoxylum: A review

Chinese prickly ash is known for producing a typical pungent sensation in Sichuan Cuisine. Accumulating evidence suggest a series of health benefits and pharmacological effects associated with prickly ash. Therefore, a systematic analysis of the composition, structural properties, detection, and flavor mechanism of numbing substances is highly necessitated to address their future application. Sanshool-based unsaturated amides are the primary cause of tingling. The numbing substances have poor stability and are prone to oxidation and decomposition reactions due to their highly unsaturated conjugated diene structures. Pungent sensations evoked by different sanshools are distinct, which is attributed to different mechanisms of interaction with membrane ion channels (TRPV1, TRPA1, and KCNK). In this paper, the composition, structural properties (such as isomerization, oxidation), detection, and flavor mechanism of numbing substances of prickly ash were summarized. The prospective application and future research direction of numbing substances in the prickly ash industry were also proposed.

New Lead Discovery of Herbicide Safener for Metolachlor Based on a Scaffold-Hopping Strategy

The use of herbicide safeners can significantly alleviate herbicide injury to protect crop plants and expand the application scope of the existing herbicides in the field. Sanshools, which are well known as spices, are N-alkyl substituted compounds extracted from the Zanthoxylum species and have several essential physiological and pharmacological functions. Sanshools display excellent safener activity for the herbicide metolachlor in rice seedlings. However, the high cost of sanshools extraction and difficulties in the synthesis of their complicated chemical structures limit their utilization in agricultural fields. Thus, the present study designed and synthesized various N-alkyl amide derivatives via the scaffold-hopping strategy to solve the challenge of complicated structures and find novel potential safeners for the herbicide metolachlor. In total, 33 N-alkyl amide derivatives (2a–k, 3a–k, and 4a–k) were synthesized using amines and saturated and unsaturated fatty acids as starting materials through acylation and condensation. The identity of all the target compounds was well confirmed by ¹H-NMR, ¹³C-NMR, and high-resolution mass spectrometry (HRMS). The primary evaluation of safener activities for the compounds by the agar method indicated that most of the target compounds could protect rice seedlings from injury caused by metolachlor. Notably, compounds 2k and 4k displayed excellent herbicide safener activities on plant height and demonstrated relatively similar activities to the commercialized compound dichlormid. Moreover, we showed that compounds 2k and 4k had higher glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO) activities in rice seedlings, compared to the metolachlor treatment. In particular, 2k and 4k are safer for aquatic organisms than dichlormid. Results from the current work exhibit that compounds 2k and 4k have excellent crop safener activities toward rice and can, thus, be promising candidates for further structural optimization in rice protection.

An Improved and Practical Method for Synthesizing of α-Sanshools and Spilanthol

An efficient and practical route for the synthesis of α-sanshools and spilanthol is described herein. Several modifications of an existing method enabled the preparation of the (2E,6Z,8E,10E)-tetraene precursor of hydroxy-α-sanshool in good yield. A highly selective Wittig reaction employing newly synthesized phosphonium salt with low deliquescence and long-term stability yielded the desired Z-form tetraene. This improved methodology was shown to be applicable to the efficient synthesis of α-sanshool and spilanthol.

Polyunsaturated fatty acid amides from the Zanthoxylum genus – from culinary curiosities to probes for chemical biology

A critical and comprehensive review of the discovery, synthesis, and biological activities of alkamides isolated from Zanthoxylum plants and synthetic derivatives thereof.