A biomimetic synthesis-enabled stereochemical assignment of rhodotomentones A and B, two unusual caryophyllene-derived meroterpenoids from Rhodomyrtus tomentosa

Abstract

Rhodotomentones A and B (1 and 2), two unusual caryophyllene-derived meroterpenoids (CDMTs) featuring a rare 6/6/9/4/6/6 hexacyclic ring system, along with their biogenetically-related CDMTs 7 and 12–15, were isolated from Rhodomyrtus tomentosa.

Total Syntheses of the Imidazo[1,2‐f]phenanthridine‐Containing Alkaloid Zephycandidine A

“…The cells were then infected with the relevant virus at 100 TCID50 in the presence or absence of the test compounds at the appropriate concentrations. At 72 h post‐infection, the virus‐induced CPEs were observed and scored using microscopy [25,26] . In the anti‐RSV assays, ribavirin was used as the positive control (IC 50 =6.9 μM, CC 50 >100 μM) and in the anti‐HSV‐1 assays acyclovir (IC 50 =0.4 μM, CC 50 >100 μM) was used for the same purpose.…”

“…The combined organic phases were then dried (Na 2 SO 4 ), filtered and concentrated under reduced pressure to afford a light-yellow oil that was subjected to flash column chromatography (silica, 1:3 v/v ethyl acetate/petroleum ether elution). Concentration of the relevant fractions (R f = 0.2) then afforded compound 12 (25…”

“…At 72 h post-infection, the virus-induced CPEs were observed and scored using microscopy. [25,26] In the anti-RSV assays, ribavirin was used as the positive control (IC 50 = 6.9 μM, CC 50 > 100 μM) and in the anti-HSV-1 assays acyclovir (IC 50 = 0.4 μM, CC 50 > 100 μM) was used for the same purpose.…”

Discovery and Biomimetic Synthesis of a Polycyclic Polymethylated Phloroglucinol Collection from Rhodomyrtus tomentosa

“…tomentosa. In particular, phloroglucinol derivatives discovered from this plant, including monomeric, dimeric, and trimeric phloroglucinols, as well as phloroglucinol–terpene adducts, have drawn increasing research interest in recent years. , …”

“…Recently, our group reported the discovery and biomimetic synthesis of a series of novel phloroglucinol derivatives from the leaves and twigs of R. tomentosa . In a further investigation on the same plant material, six pairs of enantiomeric phloroglucinol trimers with similar UV absorption and identical molecular formulas, as well as very close NMR spectral features, were discovered under the guidance of HPLC–UV–MS (Figure ).…”