Isolation and In Silico SARS-CoV-2 Main Protease Inhibition Potential of Jusan Coumarin, a New Dicoumarin from .

A new dicoumarin, jusan coumarin, (), has been isolated from aerial parts. The chemical structure of jusan coumarin was estimated, by 1D, 2D NMR as well as HR-Ms spectroscopic methods, to be 7-hydroxy-6-methoxy-3-[(2-oxo-2H-chromen-6-yl)oxy]-2H-chromen-2-one. As the first time to be introduced in nature, its potential against SARS-CoV-2 has been estimated using various in silico methods.

Jusanin, a New Flavonoid from with an In Silico Inhibitory Potential against the SARS-CoV-2 Main Protease.

A new flavonoid, Jusanin, () has been isolated from the aerial parts of . The chemical structure of Jusanin has been elucidated using 1D, 2D NMR, and HR-Ms spectroscopic methods to be 5,2',4'-trihydroxy-6,7,5'-trimethoxyflavone. Being new in nature, the inhibition potential of has been estimated against SARS-CoV-2 using different in silico techniques.

Isolation and In Silico Anti-SARS-CoV-2 Papain-Like Protease Potentialities of Two Rare 2-Phenoxychromone Derivatives from spp.

Two rare 2-phenoxychromone derivatives, 6-demethoxy-4`-O-capillarsine () and tenuflorin C (), were isolated from the areal parts of and respectively, for the first time. Being rare in nature, the inhibition potentialities of and against SARS-CoV-2 was investigated using multistage in silico techniques. At first, molecular similarity and fingerprint studies were conducted for and against co-crystallized ligands of eight different COVID-19 enzymes.

New Flavonoids from Boldoa purpurascens Cav.

Phytochemical analysis of the leaves of BOLDOA PURPURASCENS Cav. led to isolation of four flavone glycosides, three of which are new compounds. Their structures have been determined by mass spectrometry and by 1 D and 2 D NMR analysis, i.

Facile synthesis of novel indolo[3,2-b]carbazole derivatives and a chromogenic-sensing 5,12-dihydroindolo[3,2-b]carbazole.

Novel indolo[3,2-b]carbazole derivatives and a chromogenic-sensing 5,12-dihydroindolo[3,2-b]carbazole have been synthesized starting from tetra-tert-butylated 6,12-diaryl-5,11-dihydroindolo[3,2-b]carbazoles, which were prepared via an efficient tert-butylation of 6,12-diaryl-5,11-dihydroindolo[3,2-b]carbazoles.

Oxidative reactions of 6-pentyl indolo[3,2-b]carbazole: formation of novel C-C and C-N coupled dimers.

The oxidative coupling reactions of 6-pentyl-5,11-dihydroindolo[3,2-b]carbazole have been studied and as a result, a number of novel dimers of the indolo[3,2-b]carbazole derivative have been prepared, forming C-C coupled compound when treated with FeCl(3) x 6H(2)O or C-N coupled compounds and when oxidized with air or Pd(OAc)(2), respectively.

Identification of steviol glucuronide in human urine.

Stevioside (250 mg capsules) was given three times daily to 10 healthy subjects. Steviol glucuronide (steviol 19-O-beta-D-glucopyranosiduronic acid; MM, 494.58; melting point, 198-199 degrees C) was characterized in the 24 h urine as the only excretion product of oral stevioside by MS, NMR, IR, and UV spectroscopy.

Steviol quantification at the picomole level by high-performance liquid chromatography.

A simple and highly sensitive reversed-phase high-performance liquid chromatographic method (RP-HPLC) has been developed for the determination of steviol (SV) using dihydroisosteviol (DHISV) as an internal standard (IS). SV and DHISV were derivatized by reaction of the acids with 4-(bromomethyl)-7-methoxycoumarin in an aprotic solvent (DMF or acetone). The resulting ester derivatives were separated on an ODS column (250 x 4.

Reactions of 5-mercaptoazoles and pyridine-2-thiones with acetylenic esters. Selectivity of the formation of novel fused thiazin-4-ones and thiazolidin-4-ones.

A systematic study of the reactions of dimethyl acetylenedicarboxylate (DMAD) and methyl propynoate with 5-mercaptoazoles and pyridine-2-thiones has been carried out and as a result, a number of novel imidazo[1,5-b]thiazin-4-ones 6a,b, pyrazolo[1,5-b] thiazin-4-ones 15a-f, imidazo[1,5-b]thiazol-4-ones 7a,b and thiazolo[3,2-a]pyridines 21a-c have been prepared. The influence of the size of the ring of the starting "cyclic" thioamides on the size of the fused ring in the reaction products has been established. The preferred formation of a six-membered thiazine ring took place in the reactions of 5-mercaptoazoles.