Daisy H. Fleita

Novel Synthesis of Hydrazide-Hydrazone Derivatives and Their Utilization in the Synthesis of Coumarin, Pyridine, Thiazole and Thiophene Derivatives with Antitumor Activity

The reaction of cyanoacetyl hydrazine (1) with 3-acetylpyridine (2) gave the hydrazide-hydrazone derivative 3. The latter compound undergoes a series of heterocyclization reactions to give new heterocyclic compounds. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) was performed. Most of the synthesized compounds showed high inhibitory effects.

The utilization of 2-aminoprop-1-ene-1,1,3-tricarbonitrile as a precursor to quinoline, furan and thiophene derivatives with antitumor activities

Abstract The condensation reaction of 2-aminoprop-1-ene-1,1,3-tricarbonitrile (1) with 2-acetyl-furan (2) afforded 2-amino-4-(furan-2-yl)penta-1,3-diene-1,1,3-tricarbonitrile (3). The latter compound underwent a series of heterocyclization reactions to give quinoline, furan, pyrazole and thiophene derivatives. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were recorded. Three of the synthesized compounds, namely 4, 5d and 12 showed high inhibitory effects.

Uses of 5,5-Dimethyl-7-oxocyclohexeno[b]thiophene Derivatives in Heterocyclic Synthesis

Abstract The reaction of dimedone (1) with sulfur and the cyanomethylene reagents gave the cyclohexeno[b]thiophene derivatives. The reactivity of the latter products towards some chemical reagents was studied to give annulated derivatives. Their toxicity also was studied.

Gas-liquid chromatographic separation of N-trifluoroacetyl iso-butyl esters of 20 protein amino acids on a single column

ZusammenfassungDie Trennung erfolgt auf einer einzigen Mischphasensäule (OV-17∶OV-210; 2%∶1% an 100/120 Supelcoport). Die Probleme, die sich früher für die Trennung und Analyse von Histidin, Arginin, Tryptophan und Cystin ergaben, konnten dadurch überwunden werden. Das Verfahren ermöglicht eine schnelle, genaue und empfindliche Trennung und ist nützlich für die Untersuchung von Substanzen von biologischem Interesse.SummaryA procedure is established for the separation and quantitation of 20 protein amino acids by gas-chromatography in which the N-trifluoroacetyl-iso-butyl esters of these acids were chromatographically separated on a single mixed phase column OV-17 ∶ OV-210 (2%∶1% on 100/120 Supelcoport). The problems faced by previous investigators for separation and analysis of histidine, arginine, tryptophane and cystine have been solved. The procedure enables rapid, accurate and sensitive amino acid analysis and might fill an important need of scientists who are faced with the problem of amino acid analysis of biologically important substances.

Chapter 9 – Assessment of the State-of the-Art Developments in the Extraction of Antioxidants From Marine Algal Species

Abstract There is a current increasing demand for antioxidants in food, pharmaceutical, and medical applications. Bioactive compounds, particularly sulfated polysaccharides (SPs) extracted from marine algal species were found to exhibit remarkable antioxidant activities. Various extraction methods have been reported in this regard, including conventional, as well as modern techniques, such as ultrasonic-, microwave-, and enzyme-assisted extraction. These were conducted using different solvents and under varying operating conditions of temperature, time, and solvent to substrate ratio. In this review, we critically assess the state-of-the-art methods for extracting antioxidants with emphasis on SPs, from green, red, and brown algae. The evaluation will be primarily based on the yields and antioxidant activities of the extracted SPs, in addition to other technical, economic, and environmental criteria.

Crystal structure of 2-cyano-N′-(cyclo­hexyl­idene)acetohydrazide

In the title compound, C9H13N3O, the cyclohexylidene ring adopts a chair conformation and the bond-angle sum at the C atom linked to the N atom is 359.6°. The cyanoacetohydrazide grouping is close to planar (r.m.s. deviation for the non-H atoms = 0.031 Å) and subtends a dihedral angle of 64.08 (4)° with the four C atoms forming the seat of the chair. The C=O and N—H groups are in a syn conformation (O—C—N—H = −5°). In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate R 2 2(8) loops; this dimer linkage is reinforced by a pair of C—H⋯O interactions, which generate R 2 2(14) loops. The dimers are linked by C—H⋯Nc (c = cyanide) interactions into [100] ladders, which feature C(4) chains and R 4 4(20) loops.

2-(4-Oxo-3-phenyl-1,3-thia­zolidin-2-yl­idene)malononitrile

In the title compound, C12H7N3OS, the essentially planar thiazole ring (r.m.s. deviation = 0.022 Å) forms dihedral angles of 84.88 (9) and 1.8 (3)° with the phenyl ring and the –C(CN)2 group (r.m.s. deviation = 0.003 Å), respectively. The molecule has approximate local C s symmetry. In the crystal, molecules are linked via C—H⋯N hydrogen bonds, forming chains propagating along [101]. The crystal studied was found to be an inversion twin with a refined 0.63 (1):0.37 (1) domain ratio.