Alan Ford,† Hugues Miel, Aoife Ring,† Catherine N. Slattery,† Anita R. Maguire,*,†,‡ and M. Anthony McKervey* †Department of Chemistry and ‡School of Pharmacy, Analytical and Biological Chemistry Research Facility, Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland Almac Discovery Ltd., David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom Almac Sciences Ltd., Almac House, 20 Seagoe Industrial Estate, Craigavon BT63 5QD, United Kingdom

Modern Organic Synthesis with α-Diazocarbonyl Compounds

Ethylenediamine diacetate-catalyzed three-component reaction for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones and their spirooxindole derivatives

‡Efficient one-pot synthesis of arylmethylene bis(3-hydroxy-2-cyclohexene-1-ones) and xanthenediones by EDDA and In(OTf)3-catalyzed reactions was developed starting from dimedone and aryl aldehydes. The key strategies of these reactions involve domino Knoevenagel/Michael reaction or Koevenagel/Michael/Cyclodehydration reactions. The scope and limitation of the two catalysts under various reaction conditions were investigated and described.

http://koreascience.or.kr:80/article/JAKO200902727120642.pdf

New and General Methods for the Synthesis of Arylmethylene Bis(3-Hydroxy-2-Cyclohexene-1-Ones) and Xanthenediones by EDDA and In(OTf)3-Catalyzed One-Pot Domino Knoevenagel/Michael or Koevenagel/Michael/Cyclodehydration Reactions

Ten flavonoid-related structures viz. heliteretifolin (1), isoxanthohumol (2), 2',4',6'-trihydroxy-3'-prenylchalcone (3), isoglabranin (4), glabranin (5), 7-methoxy-isoglabranin (6), quercetin (7), 4'-methoxyquercetin (8), 4'-methoxykaempferol (9) and mosloflavone (10) were isolated from a H. teretifolium methanolic extract and identified. One of them (compound 1) is reported for the first time from a natural source, while compounds 6, 8–10 were isolated for the first time from the genus Helichrysum. The total extract of H. teretifolium showed potent antioxidant activity. When tested for total antioxidant capacity compound 3 possesses moderate biological activity compared to 2, which displayed some of the highest TEAC values (4529.01 ± 2.44; 4170.66 ± 6.72) µM TE/g, respectively. Compounds 7 and 8 demonstrated the highest inhibitory activities on Fe2+-induced lipid peroxidation (IC50 = 2.931; 6.449 µg/mL); tyrosinase (8.092; 27.573) and elastase (43.342; 86.548). Additionally, the total antioxidant capacities measured as FRAP (4816.31 ± 7.42; 3584.17 ± 0.54) µM AAE/g, and ORAC for hydroxyl radical (7.265 ± 0.71; 6.779 ± 3.40) × 106 and peroxyl radical (17.836 ± 2.90; 12.545 ± 5.07) × 103 µM TE/g were also observed for compounds 7 and 8, respectively. In conclusion, H. teretifolium total extract represents a rich source of bioactive constituents with potent antioxidant and moderate anti-tyrosinase and anti-elastase activities that can help to avert accumulation of free radicals in the body, and could therefore be good candidates for the prevention and/or treatment of skin-related conditions, such as aging. This is the first scientific report on the chemical and biological profile of H. teretifolium.

https://www.mdpi.com/1420-3049/20/4/7143/pdf

Inhibition of Oxidative Stress and Skin Aging-Related Enzymes by Prenylated Chalcones and Other Flavonoids from Helichrysum teretifolium

The cannabis plant has had a tumultuous past. Once revered for its medicinal properties, it then became a banned narcotic and now the perceived medical benefits of cannabis see it receiving renewed attention. The active ingredients in cannabis plant extracts — phytocannabinoids — are now being investigated, both as formulations and in isolation, for pharmaceutical applications. The most abundant phytocannabinoid is (−)-trans-Δ9-tetrahydrocannabinol, a compound readily extracted from Cannabis sativa. There are over 100 known phytocannabinoids, some of which are present in such low concentrations that chemical syntheses are necessary to advance their medicinal potential. In this Review, we examine phytocannabinoids in terms of their mode of action, biosynthesis, and various total syntheses and derivatizations. Finally, we describe the policy issues surrounding the possession, use and control of phytocannabinoids. Some plant-derived ligands for the cannabinoid receptors — phytocannabinoids — are promising pharmaceuticals. This Review covers the chemical synthesis of phytocannabinoids and metabolites to enable the study of compounds otherwise inaccessible on a practical scale. Availability of drug candidates is also hindered by policy issues, which we discuss with regard to possession, use and control.

The evolving science of phytocannabinoids

This paper describes a new and efficient synthetic approach for biologically interesting natural mallotophilippens C and E. The key strategies involved ethylenediamine diacetate-catalyzed benzopyran formation reactions and base-catalyzed aldol reactions.

/pdf/concise-total-synthesis-of-biologically-interesting-48q8xd1q7e.pdf

Concise total synthesis of biologically interesting mallotophilippens C and e.

Simple and facile synthetic routes for the preparation of biologically interesting cyclol bearing polycycles were developed using FeCl3-promoted [2 + 2] cycloaddition from readily available benzopyrans possessing a variety of substituents. As examples of this methodology, one-step syntheses of cannabicyclol, cannabicyclovarin, and ranhuadujuanine A were accomplished in good yield.

Efficient and novel one-pot synthesis of polycycles bearing cyclols by FeCl3-promoted [2 + 2] cycloaddition: application to cannabicyclol, cannabicyclovarin, and ranhuadujuanine A

Efficient one-pot synthesis of cyclic β-enaminoamides by thermal Wolff rearrangement of cyclic 2-diazo-1,3-dicarbonyls and conversion to uracil derivatives

There is still a demand fora more convenient and efficient synthetic method that canefficiently provide quinazoline-2,4-dione derivatives. Wereport herein a convenient one-pot synthesis of quinazoline-2,4-dione derivatives. We also report on the synthesis of thenaturally occurring alkaloids 2 and 3. Results and DiscussionA two-step reaction for the synthesis of quinazoline-2,4-dione derivatives starting from isatoic anhydride and amineshas already been described.

/pdf/facile-one-pot-synthesis-of-quinazoline-2-4-dione-9d7f6qomky.pdf

Facile One-Pot Synthesis of Quinazoline-2,4-dione Derivatives and Application to Naturally Occurring Alkaloids from Zanthoxylum Arborescens

This paper describes a new synthetic approach for biologically interesting geranylated acetophenones. The first total syn- theses of 1-(5-geranyloxy-7-hydroxy-2,2-dimethyl-2H-chromen-8-yl)ethanone and 1-(5-geranyloxy-7-hydroxy-2- methyl-2-(4-methylpent-3-enyl)-2H-chromen-8-yl)ethanone, isolated from Melicope semecarpifolia, were carried out starting from commercially available 2,4,6-trihydroxyacetophenone.

/pdf/new-synthetic-routes-to-biologically-interesting-geranylated-45qo86e0mg.pdf

New Synthetic Routes to Biologically Interesting Geranylated Acetophenones from Melicope Semecarpifolia and Their Unnatural Prenylated and Farnesylated Derivatives

Xin Li

Papers

Concise total synthesis of biologically interesting mallotophilippens C and e.

Efficient and novel one-pot synthesis of polycycles bearing cyclols by FeCl3-promoted [2 + 2] cycloaddition: application to cannabicyclol, cannabicyclovarin, and ranhuadujuanine A

Efficient one-pot synthesis of cyclic β-enaminoamides by thermal Wolff rearrangement of cyclic 2-diazo-1,3-dicarbonyls and conversion to uracil derivatives

Facile One-Pot Synthesis of Quinazoline-2,4-dione Derivatives and Application to Naturally Occurring Alkaloids from Zanthoxylum Arborescens

New Synthetic Routes to Biologically Interesting Geranylated Acetophenones from Melicope Semecarpifolia and Their Unnatural Prenylated and Farnesylated Derivatives