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Abstract In one pot, the self-assembly of AgNO3 and 2-chloroquinoxaline (2Cl-quinox) in water–ethanol mixture afforded two novel crystalline Ag(I) complexes. The major product is the polymeric complex [Ag(2Cl-quinox)(NO 3 )] n ; (1), while the minor product (2) comprises two molecules which are the monomeric [Ag(2Cl-quinox) 2 (NO 3 )]; (2a) and polymeric [Ag(2Cl-quinox)(NO 3 )] n ; (2b) complexes. The single crystal X-ray structure revealed that 1 and 2b are made up of two-dimensional infinite sheets. In contrast, 2a is a monomeric complex which has a highly distorted tetrahedral geometry around Ag(I) center. In all cases, the 2Cl-quinox molecule acts as a terminal monodentate ligand. Complexes 1 and 2b have similar molecular structures and also have almost similar crystal packing. Using Hirshfeld surface analysis, the O…H hydrogen bonds and π–π stacking interactions contributed significantly to the molecular packing. Both complexes have broad-spectrum action towards multi drug-resistance bacteria. The most effective function of 2 is against Proteus morganii, with a MIC value of 8 μg/mL. Complex 2 (IC50 = 5.93 ± 0.52 μg/mL) has remarkably greater cytotoxic effect against lung carcinoma (A-549) than cis-platin (IC50 = 7.5 ± 0.69 μg/mL) and AgNO3 (IC50 = 14.7 ± 0.53 μg/mL). The higher Ag-content in 2 could be the main reason for its higher cytotoxicity than 1.

A new Ag(I) adduct was synthesized by the reaction of 4-amino-4H-1,2,4-triazole (L) with AgNO3. Its chemical structure was approved to be [Ag2(L)2(NO3)]n(NO3)n utilizing elemental analysis, FTIR spectra, and single crystal X-ray diffraction (SC-XRD). According to SC-XRD, there are two independent silver atoms which are coordinated differently depending on whether the nitrate anion is coordinated or not. The coordination geometry of Ag1 is a slightly bent configuration while Ag2 has a distorted tetrahedral structure. The 4-amino-4H-1,2,4-triazole ligand and one of the nitrate groups adopt bridging mode, which connects the crystallographically independent Ag1 and Ag2 atoms resulting in the formation of two-dimensional coordination polymer. Hirshfeld surface analysis displays that the intermolecular O···H (34.0%), Ag···N (10.6%), H···H (10.4%), Ag···O (9.3%), and N···H (9.0%) contacts are the most abundant interactions. Regarding anticancer activity, the [Ag2(L)2(NO3)]n(NO3)n demonstrates stronger cytotoxic efficacy against lung (IC50 = 3.50 ± 0.37 µg/mL) and breast (IC50 = 2.98 ± 0.26 µg/mL) carcinoma cell lines than the anticancer medication cis-platin. The [Ag2(L)2(NO3)]n(NO3)n complex showed interesting antibacterial and antifungal activities compared to the free components (AgNO3 and 4-amino-4H-1,2,4-triazole). The investigated silver(I) complex exhibits remarkable antibacterial activity against E. coli (MIC = 6.1 µg/mL) that may be on par with Gentamycin (MIC = 4.8 µg/mL). As a result, the newly synthesized Ag(I) complex could be suggested for anticancer and antibacterial treatments.

The [Ag(3ADMT)(NO3)]n complex was synthesized by the self-assembly of 3-amino-5,6-dimethyl-1,2,4-triazine (3ADMT) and AgNO3. Its molecular structure was analyzed utilizing FTIR spectra, elemental analysis, and single crystal X-ray diffraction (SC-XRD). There is one crystallographically independent Ag atom, which is tetra-coordinated by two nitrogen atoms from two 3ADMT and two oxygen atoms from two nitrate anions where all ligand groups are acting as connectors between the Ag1 sites. The geometry around the Ag(I) center is a distorted tetrahedron with a AgN2O2 coordination sphere augmented by strong argentophilic interactions between Ag atoms, which assist the aggregation of the complex units in a wavy-like and coplanar pattern to form a one-dimensional polymeric chain. The O...H (37.2%) and N...H (18.8%) intermolecular interactions contributed significantly to the molecular packing based on Hirshfeld surface analysis. The [Ag(3ADMT)(NO3)]n complex demonstrates promising cytotoxicity against lung (IC50 = 2.96 ± 0.31 μg/mL) and breast (IC50 = 1.97 ± 0.18 μg/mL) carcinoma. This remarkable cytotoxicity exceeds those of 3ADMT, AgNO3, and the anticancer medication cis-platin towards the tested cancer cell lines. In addition, the complex has a wide-spectrum antimicrobial action where the high antibacterial potency of the [Ag(3ADMT)(NO3)]n complex against P. vulgaris (MIC = 6.1 µg/mL) and B. subtilis (MIC = 17.2 µg/mL) could be comparable to the commonly used drug Gentamycin (MIC = 4.8 µg/mL). These results confirm that the components of the [Ag(3ADMT)(NO3)]n complex work together synergistically, forming a powerful multifunctional agent that could be exploited as an effective antimicrobial and anticancer agent.

A novel Ag(I) citrate complex with ethyl-3-quinolate (Et3qu) was synthesized. Its structure was confirmed using X-ray single crystal to be [Ag(Et3qu)2(citrate)]. It crystallized in the Triclinic crystal system and P-1 space group with unit cell parameters of a = 8.6475(2) Å, b = 11.4426(3) Å, c = 15.2256(3) Å, α = 73.636(2)°, β = 79.692(2)° and γ = 86.832(2)°, while the unit cell volume was 1422.19(6) Å3. In the unit cell, there are two [Ag(Et3qu)2(citrate)] molecules and one unit as the asymmetric formula. The molecular structure comprised one Ag(I) coordinated with two Et3qu molecules via two almost equidistant Ag-N bonds and one citrate ion acting as a mono-negative monodentate ligand via a short Ag-O bond (2.5401(14) Å). Hence, Ag(I) is tri-coordinated and has a highly distorted triangular planar coordination geometry which is more like to be described as a slightly distorted T-shape. The supramolecular structure of the [Ag(Et3qu)2(citrate)] complex was analyzed using Hirshfeld calculations. The H···H (39.3–40.1%), O···H (33.2-34.0%), C···C (9.1–9.5%) and C···H (7.2–7.4%) contacts shared significantly in the packing of the studied Ag(I) complex. The antimicrobial and anticancer activities of the Ag(I) complex were investigated. The [Ag(Et3qu)2(citrate)] complex has broad-spectrum antimicrobial activity specifically against the fungus A. fumigatus. In addition, the IC50 values of 1.87 ± 0.09 µg/mL and 0.95 ± 0.06 µg/mL against the breast MCF-7 and lung A-549 cell lines, respectively, revealed the potent anticancer activity of the [Ag(Et3qu)2(citrate)] complex compared to the free Et3qu (IC50 = 30.64 ± 1.98 and 22.89 ± 1.48 µg/mL, respectively).

Background : Jazan province is located in the south-west of the Kingdom of Saudi Arabia. The province is offlicted with a wide spectrum of diseases and therefore have a special need for more health services. The Faculty of Medicine at Jazan has been following the traditional curriculum since its inception in 2001. The traditional curriculum has been criticized because of the students inability to relate what they learned in the basic sciences to medicine, thus stifling their motivation. It was felt that much of what was presented in preclinical courses was irrelevant to what the doctor really needed to know for his practice. The College therefore, decided to change to an integrated curriculum. Design: The study was conducted in 2004-2005 in the Faculty of Medicine, Jazan University. It began with a literature survey/search for relevant information and a series of meetings with experts from various institutions. A Curriculum Committee was formed and a set of guiding principles was prepared to help develop the new curriculum. A standard curriculum writing format was adopted for each module. It was decided that an independent evaluation of the new curriculum was to be done by experts in medical education before submission for official approval. There were several difficulties in the course of designing the curriculum, such as: provision of vertical integration, the lack of preparedness of faculty to teach an integrated curriculum, and difficulties inherent in setting a truly integrated examination. Curriculum: The program designed is for 6 years and in 3 phases; pre-med (year 1), organ/system (years 2 and 3), and clinical clerkship (years 4, 5, and 6). This is to be followed by a year of Internship. The pre-med phase aims at improving the students′ English language and prepare them for the succeeding phases. The organ/ system phase includes the integrated systems and the introductory modules. The curriculum includes elective modules, early clinical training, behavioral sciences, medical ethics, biostatistics, computer practice, and research methods. The curriculum provides active methods of instruction that include: small group discussion/ tutorials, problem-based learning (PBL), case-study/ clinical presentations, seminars, skills practice (clinical skill lab), practical, demonstration, and student independent learning. Methods of evaluating students include continuous and summative assessment. Conclusion: The new curriculum adopted by the Jazan Faculty of Medicine is an integrated, organ/ system based, community-oriented, with early clinical skills, elective modules, and innovative methods of instructions.