Polyprenylated Acylphloroglucinols With Different Carbon Skeletons From the Fruits of Garcinia multiflora

Abstract

Eleven new polycyclic polyprenylated acylphloroglucinols (PPAPs, 1–11) and three new monocyclic polyprenylated acylphloroglucinols (MPAPs, 12–14), together with ten known analogues were isolated from the fruits of Garcinia multiflora. These PPAPs belong to three types including the bicyclic polyprenylated acylphloroglucinols (BPAPs), the caged PPAPs, and the complicated PPAPs. Their structures and absolute configurations were determined through HRESIMS, NMR spectroscopy data, electronic circular dichroism (ECD) calculations, and gauge-independent atomic orbital (GIAO) NMR calculations with DP4+ analyses. Moreover, compounds 2 and 7 exhibited moderate cytotoxicity against three human cancer lines (MCF-7, T98, and HepG2) with IC50 values ranging from 9.81 ± 1.56 to 17.00 ± 2.75 μM.

Garbractin A, a Polycyclic Polyprenylated Acylphloroglucinol with a 4,11-dioxatricyclo[4.4.2.01,5]Dodecane Skeleton from Garcinia bracteata Fruits

“…Comparison of the NMR data of compounds 5 and 6 with those of garcibracteatone and doitunggarcinone A revealed that compounds 5 and 6 contain ( E )-3-hydroxy-3-methylbut-1-en-1-yl groups at C-3, instead of a prenyl group at C-3 in garcibracteatone and doitunggarcinone, respectively. This was further confirmed by the HMBC correlations from H-14 and H-15 to C-3, , and the configuration of the double bond Δ 24(25) was assigned the E on the basis of the coupling constant value of 16.2 Hz between H-14 and H-15 . The relative configurations of 5 and 6 were also assigned as the same as those of compounds 2 – 4 based on the ROESY spectrum.…”

“…This was further confirmed by the HMBC correlations from H-14 and H-15 to C-3, 11 , 12 and the configuration of the double bond Δ 24(25) was assigned the E on the basis of the coupling constant value of 16.2 Hz between H-14 and H-15. 17 The relative configurations of 5 and 6 were also assigned as the same as those of compounds 2 – 4 based on the ROESY spectrum.…”

Nuclear Magnetic Resonance

“…Polyprenylated acylphloroglucinols were isolated from the fruits of Garcinia multiflora and their structure, together with absolute configuration determined by NMR, were supported using molecular modeling and GIAO calculations combined with the DP4þ methodology. 85 New debromoaplysiatoxin analogues 86 were isolated from marine Cyanobacterium Lyngbya sp. and their absolute configuration confirmed by X-ray studies and GIAO NMR calculations.…”