Fullerene derivative as anti-HIV protease inhibitor: molecular modeling and QSAR approaches.

A Fullerene based system is modified in order to increase its solubility and enhance its ability to carry a protein-like structure. The modified structure, which is proposed to act as HIV-1 protease inhibitor, is [C60-C2H4N-(2,4- XCOCH2OH)C6H4], where the X atom is either O, S or Se. The geometry optimization, vibrational spectra and thermodynamics were performed using semiempirical quantum mechanical PM3 method in order to study the proposed compounds. Furthermore, the quantitative structure activity relationship (QSAR) properties of the compounds are calculated at the same level of theory. Results indicate a possible use of the investigated structures as HIV-1 protease inhibitors. The compounds containing oxygen is more stable as compared to the other two compounds.

Two new flavonoids from Retama raetam.

Two new flavones were isolated from the aerial parts of Retama raetam subsp. raetam. Their structures were established as luteolin 4'-O-neohesperidoside (1) and 5,4'-dihydroxy-(3",4"-dihydro-3", 4"-dihydroxy)-2",2"-dimethylpyrano-(5",6":7,8)-flavone (2) by means of spectroscopic methods. Also present was ephedroidin (4',5, 7-trihydroxy-8-(2-hydroxy-3-butenyl)-flavone).

New flavonoids from Avicennia marina.

In addition to luteolin 7-O-methylether, chrysoeriol 7-O-glucoside and isorhamnetin 3-O-rutinoside, the methanol extract of the aerial parts of Avicennia marina yielded two new flavonoids identified as luteolin 7-O-methylether 3'-O-beta-D-glucoside and its galactoside analogue 2.

Quercetin triglycoside from Capparis spinosa.

In addition to rutin, quercetin 3-O-glucoside and quercetin 3-O-glucoside-7-O-rhamnoside, the methanolic extract of the aerial parts of Capparis spinosa yielded the new flavonoid quercetin 3-O-[6'"-alpha-L-rhamnosyl-6"-beta-D-glucosyl]-beta-D-glucoside (1).

Four flavonoid glycosides from Peganum harmala.

The aerial parts of Peganum harmala yielded four new flavonoids: acacetin 7-O-rhamnoside, 7-O-[6"-O-glucosyl-2"-O-(3'''-acetylrhamnosyl)glucoside and 7-O-(2'''-O-rhamnosyl-2"-O-glucosylglucoside), and the glycoflavone 2'''-O-rhamnosyl-2"-O-glucosylcytisoside.

Biochemical changes associated with acute phosphorus poisoning (in humans).

1. Thirty patients with acute phosphorus poisoning (APP) were chosen from the poison control centre, Cairo (PCCC), Ain Shams University, and classified into three groups according to the amount of ingested inorganic phosphorus (Pi). 2. Group I recorded high mortality rate (90%) with liver failure as a main cause of death. This group also showed hepatorenal failure, hypoglycemia and severe effect on the heart function. 3. Groups II and III recorded no mortality, but their patients showed an effect on the liver, which was severe in group II and mild in group III.

New inhibitors for aminoglycoside-adenylyltransferase.

Two hydroxymethyltropolones and two tropolone acetate derivatives were found to inhibit an aminoglycoside-adenylyltranferase in a gentamicin-resistant Escherichia coli strain. The inhibitory effect of tropolones depends on the nature of the aminoglycoside antibiotic subject to adenylation. Combinations of hydroxymethyltropolones with tobramycin were more active compared with tropolone acetates against gentamicin-resistant strains displaying adenylyltransferase activity. On the contrary a combination of the investigated acetate with gentamicin was of lower activity. It could be shown that these inhibitors inhibit, to a varying degree, the transfer of radioactive ATP to different aminoglycoside molecules.

Antibacterial activity of selected tropones and tropolones.

The antibacterial activity of 33 substituted and unsubstituted seven-member ring tropones and tropolones was examined on 14 reference strains representing Gram-positive and Gram-negative bacteria. It was shown that the chemical character and position of the substituent plays a distinct role in the biological activity of investigated compounds. Depending on the substituent the antibacterial effect may be either increased or diminished. C-1 thio and C-2 nitro derivatives of tropone are significantly more active than tropone. The dibenzotropone derivatives display no antibacterial activity. Hydroxymethyl derivatives of tropolone are more active than tropolone, while hydroxy-, isopropyl-, methyl- as well as tropolone acetates are equipotent.

UDP-Glucose: Cyanidin 3-O-glucosyltransferase from cell cultures of Haplopappus gracilis.

From cell cultures of Haplopappus gracilis, an enzyme, catalyzing the glucosylation of cyanidin at the 3 position using uridine diphosphate-D-glucose (UDPG) as glucosyl-donor, has been isolated and purified 50-fold. The enzyme was not specific for cyanidin alone, but also glucosylated other anthocyanidins and flavonols in position 3. However, apigenin, luteolin, naringenin and dihydroquercetin were not glucosylated. The reaction has an optimum pH of approximately 8, and the apparent K m values for UDPG and cyanidin were 0.5 and 0.33 mM respectively. The enzyme reaction is strongly inhibited by cyanidin (above 0.25 mM).