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Polyhydroquinoline (PHQ) are the unsymmetrical Hantzsch derivatives of 1,4-dihydropyridines with several biological applications. In this work, twenty-five (3–27) new Schiff’s base derivatives of polyhydroquinoline hydrazide were synthesized in excellent to good yields by a multi-component reaction. The structures of the synthesized products (1–27) were deduced with the help of spectroscopic techniques, such as 1H-, 13C -NMR, and HR-ESI-MS. The synthesized products (1–27) were tested for their antibacterial and in vitro calcium -channel-blocking (CCB) potentials using the agar-well diffusion method, and isolated rat aortic ring preparations, respectively. Among the series, sixteen compounds were found to inhibit the growth of Escherichia coli and Enterococcus faecalis. Among them, compound 17 was observed to be the most potent one at a dose 2 µg/mL, with an 18 mm zone of inhibition against both bacteria when it was compared with the standard drug amoxicillin. Eight compounds showed CCB activity of variable potency; in particular, compound 27 was more potent, with an EC50 value of 0.7 (0.3–1.1) µg/mL, indicating their CCB effect.

Four new pregnane glycosides named desflavasides A-D ( 1–4 ) were isolated from the sap of Desmidorchis flava (N.E.Br) Meve & Liede. The structures of all new compounds were elucidated based on 1D and 2D NMR spectroscopic techniques coupled with mass spectromentry (ESIMS and HRESIMS).

Palladium-catalyzed chemoselective and regioselective cross-coupling reactions of 2,3-dichloro-1,4-(trifluoromethanesulfonyloxy)naphthalene with aryl boronic acids selectively afforded a variety of mono-, di-, and tetraphenylnaphthalenes. These reactions proceeded with excellent chemoselectivity in favor of the triflate functional group at the C-1 and C-4 positions of naphthalene.

The assessment here includes data on levels of contaminants (petroleum hydrocarbons and heavy metals) in sediments and biomonitor organisms, including the eulittoral rock oyster Saccostrea cucullata and subtidal biomonitors, the barnacle Balanus trigonus and the antipatharian coral Antipathes sp., at harbours, marinas, terminals and large ports along the coastline of Oman. TBT levels in harbour and port sediments up to a maximum of 100 ppb TBT dry weight are highlighted. Oysters contained concentrations up to 367 ppm mg TPH/kg dry weight. The maximum levels of Cd, Cu, Pb and Zn were found in the subtidal sediments and barnacles at the oil tanker loading Single Buoy Mooring stations in Mina Al Fahal. In general, the levels of most of the contaminants analysed are at low to moderate concentrations compared to those in highly contaminated sites such as shipyards and dry docks, but continued monitoring is recommended especially during any dredging campaigns.

Palladium-catalyzed chemoselective and regioselective cross-coupling reactions of 2,3-dichloro-1,4-(trifluoromethanesulfonyloxy)naphthalene with aryl boronic acids selectively afforded a variety of mono-, di-, and tetraphenylnaphthalenes. These reactions proceeded with excellent chemoselectivity in favor of the triflate functional group at the C-1 and C-4 positions of naphthalene.

Bruising is the most common type of mechanical damage affecting fresh horticultural produce. Several mechanical devices have been reported in the literature for assessing fruit susceptibility to bruising. However, a major limitation of existing devices is the lack of objective measure of the rebound height, which is required to determine the actual impact energy absorbed during damage. In the present study, a new device was designed and developed for objective determination of the rebound height during a pendulum test for bruise susceptibility of whole produce specimens. Using a video camera as an objective benchmark, the new device compared favourably better than subjective visual assessment of the rebound height. The new device provides a simple and cost‐effective tool for fruit impact damage research and education.