The bioactivity-guided examination of a Leptolyngbya sp. led to the isolation of leptazolines A–D (1–4), from the culture media, along with two degradation products (5 and 6). Density functional theory nuclear magnetic resonance calculations established the relative configurations of 1 and 2 and revealed that the calculated shifts depended on the operating system when using the “Willoughby–Hoye” Python scripts to streamline the processing of the output files, a previously unrecognized flaw that could lead to incorrect conclusions.

Several known sesquiterpenoid quinones and quinols (1–9), and kauamide (10), a new polyketide-peptide containing an 11-membered heterocycle, were isolated from the extracts of the Hawaiian marine sponge Dactylospongia elegans. The planar structure of 10 was determined from spectroscopic analyses, and its relative and absolute configurations were established from density functional theory (DFT) calculations of the GIAO NMR shielding tensors, and advanced Marfey’s analysis of the N-MeLeu residue, respectively. Compounds 1 and 3 showed moderate inhibition of β-secretase 1 (BACE1), whereas 1–9 exhibited moderate to potent inhibition of growth of human glioma (U251) cells. Compounds 1–2 and 4–7 were also active against human pancreatic carcinoma (Panc-1) cells.

Cannabis sativa has long been known to affect numerous biological activities. Although plant extracts, purified cannabinoids, or synthetic cannabinoid analogs have shown therapeutic potential in pain, inflammation, seizure disorders, appetite stimulation, muscle spasticity, and treatment of nausea/vomiting, the underlying mechanisms of action remain ill-defined. In this study we provide the first comprehensive overview of the effects of whole-plant Cannabis extracts and various pure cannabinoids on store-operated calcium (Ca2+) entry (SOCE) in several different immune cell lines. SOCE is one of the most significant Ca2+ influx mechanism in immune cells and it is critical for the activation of T lymphocytes, leading to the release of pro-inflammatory cytokines and mediating inflammation and T cell proliferation, key mechanisms for maintaining chronic pain. While the two major cannabinoids cannabidiol (CBD) and trans-Δ9-tetrahydrocannabinol (THC) were largely ineffective in inhibiting SOCE, we report for the first time that several minor cannabinoids, mainly the carboxylic acid derivatives and particularly the cannabigerolic acid (CBGA), demonstrated high potency against SOCE by blocking Calcium Release-Activated Calcium (CRAC) currents. Moreover, we show that this inhibition of SOCE resulted in a decrease of Nuclear Factor of Activated T-cells (NFAT) activation and Interleukin 2 (IL-2) production in human T lymphocytes. Taken together, these results indicate that cannabinoid-mediated inhibition of a pro-inflammatory target such as SOCE may at least partially explain the anti-inflammatory and analgesic effects of Cannabis.