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Nanolobatone A, featuring an unprecedented tricyclo[10.3.0.0 1,2 ]pentadecane carbon skeleton, along with four new polyoxygenated and four unusual endoperoxide-bridged casbane-type diterpenoids were isolated from the Hainan soft coral Sinularia nanolobata. The structures of the new compounds were established by extensive spectroscopic analysis, X-ray diffraction analysis, and time-dependent density functional theory/electronic circular dichroism calculations. A plausible biosynthetic pathway of new isolates was proposed. Bioassays revealed that nanolobatone A showed weak antibacterial activity against the Gram-positive bacteria Streptococcus pyogenes., (© 2023 Wiley-VCH GmbH.)

Applying the emerging molecular networking strategy, an uncommon cembranoid orthoester, sarcotortin A (1), featuring a 3/14/8/5-fused scaffold, an unusual eunicellane-type diterpenoid, sarcotorolide A (2), and two new biscembranoids, ximaolides M and N (7 and 8), along with nine known terpenoids 3-6 and 9-13 were isolated from the Hainan soft coral Sarcophyton tortuosum. The structure and absolute configuration of all new compounds were established by a combination of spectroscopic data, X-ray diffraction analysis, and/or quantum chemical computational approaches. The plausible biogenetic relationship among these skeletally different terpenoids was proposed and discussed. In in vitro bioassay, new compound 7 exhibited a remarkable inhibitory activity against protein tyrosine phosphatases 1B (PTP1B) with the IC 50 value of 8.06 μM. In addition, compounds 4 and 10 displayed significant inhibitory effects on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages cells with the IC 50 values of 19.13 and 16.45 μM, respectively. Compound 9 showed interesting cytotoxicity against H1975, MDA-MB231, A549, and H1299 cancer cell lines with IC 50 values of 31.59, 34.96, 43.87, and 27.93 μM, respectively., (© 2022 Wiley-VCH GmbH.)

An amine-containing non-interpenetrating pillar-layer framework, [Zn 2 (dbtcb)(L1)]⋅x solvent (1), has been synthesized from Zn(NO 3 ) 2 and the ligands 1,4-dibromo-2,3,5,6-tetrakis(4-carboxyphenyl)benzene (H 4 DBTCB) and 2,5-bis(4-pyridyl)aniline (L1). The [Zn 2 (COO) 4 ] secondary building units (SBUs) are bridged by DBTCB to form two-dimensional layers that are linked by L1 ligands acting as pillars to form a three-dimensional network. This NH 2 -containing framework can undergo versatile tailoring through post-synthetic covalent modification, solvent-assisted linker exchange (SALE), and single-crystal-to-single-crystal (SC-SC) transmetalation reactions. Acetamide-functionalized [Zn 2 (L2)(dbtcb)]⋅xsolvent (2) could be obtained by direct synthesis from Zn(NO 3 ) 2 , N-acetyl-2,5-bis(4-pyridyl)aniline (L2) and H 4 DBTCB. Importantly, compound 1 with pure NH 2 ligands as pillars could be obtained by SALE of 2 with L1 in DMSO solution. The transmetalation reactions of 1 with Cu II , Ni II , and Co II were studied; inductively coupled plasma-atomic emission (ICP) analysis revealed that 1 underwent almost complete SC-SC transmetalation with Cu II within 30 h, whereas with Ni II and Co II only 70 and 80 % substitutions were achieved. Photoluminescence studies revealed that 1 and 2 display yellow-green and UV emission, respectively, under a UV lamp. Furthermore, the photoluminescent properties could be tuned by introducing mixed pillar amino ligands L1 and L2 into the MOF to produce multivariate (MTV) MOF 3 displaying overall orange emission., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)