The biological activity of podophyllotoxin has been expressed in terms of the alkylating potential of its “swinging lactone” functionality. The synthesis and characterization of the two isomeric lactones (X and XI) of 3-hydroxymethyl-4-(3,4-methylenedioxyphenyl)-4-hydroxybutanoic acid, embodyi...

Various lipases have been investigated for their potential use as catalysts for the resolution of esters of 4-chloro-3-hydroxybutanoic acid via transesterification in organic solvents. Rhizomucor miehei lipase was found to be the most efficient lipase, with the enantiomeric ratio (E) being depen...

Quaternary and binary blends of l- and d-configured poly(2-hydroxybutanoic acid)s [P(L-2HB) and P(D-2HB), respectively] and l- and d-configured poly(2-hydroxy-3-methylbutanoic acid)s [P(L-2H3MB) and P(D-2H3MB), respectively] were prepared by solution-casting to have fixed ratios of P(L-2HB)/P(D-...

This article describes our preliminary screening results of yeasts and fungi isolated from exotic environments like the Atlantic rain forest, from the roots of Araucaria angustifolia and from a Guava tree. Rhodotorula glutinis CCT 2182 and Cunninghamella echinulata CCT 4259 revealed high enantio...

A new β-hydroxy amino acid isolated from the fruiting bodies of Lyophyllum ulmarium was identified as Ds,-erythro-2-amino-4-ethoxy-3-hydroxybutanoic acid by chemical degradation and spectroscopic analyses.

A novel structural analogue of kynurenine, 2-amino-4-[3′-hydroxyphenyl]-4-hydroxybutanoic acid 6, was synthesised as an inhibitor of kynureninase. The compound had a significant inhibitory effect on kynureninase from both rat and human, giving a Ki of 100 nM. It was thus found that removal of t...

The R- and S-enantiomers of 4-amino-3-hydroxybutanoic acid (GABOB) were full agonists at human recombinant ρ1 GABAC receptors. Their enantioselectivity (R > S) matched that reported for their agonist actions at GABAB receptors, but was the opposite to that reported at GABAA receptors (S > R). T...

A series of readily accessible 4-arylimino-3-hydroxybutanoic acids have been prepared and evaluated as potential HIV-1 Integrase inhibitors. None of the ligands exhibited significant toxicity against human embryonic kidney (HEK 293) cells, while five of them showed activity against HIV-1 integra...

An analogue (6) of a specific anti-HIV-1 lead, 1-[(2-hydroxyethoxy)-methyl]-6-(phenylthio)thymine (1 : HEPT), has been synthesized with an aim to provide a tool that could be used as a specific photoaffinity labelling reagent for the HIV-1 reverse transcriptase.

A novel series of substituted N-(2-(2,3-dioxoindolin-1-yl)acetyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxamide was designed, synthesized and evaluated for in vitro Reverse Transcriptase (RT) inhibitory activity. This series is a combination of peculiar structural features from leading scaffo...

1-[(2-Hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) has recently proved to be a potent and selective inhibitor of human immunodeficiency virus type 1 (HIV-1) in vitro. Combinations of HEPT and recombinant alpha interferon (IFN-α) synergistically inhibit the replication of HIV-1 in MT-4 cel...

Current challenges to antiretroviral therapy have opened new vistas in the search for novel drugs from natural products. This review focusses on plants as sources of inhibitors for human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. Based on a systematic search of the literature, ...

[E]-6-(2-Acylvinyl)uracils and their corresponding 1-(2-hydroxyethoxy)methyl derivatives were synthesized through palladium-catalyzed reactions which involved an interesting rearrangement. Some of the acylvinyl uracils (3, 4, and 5) and the acyclonucleosides (8 and 10) showed pronounced activity...

A solvent-free, eco-friendly and facile approach for the synthesis of highly functionalized tetrasubstituted pyrroles has been reported through one-pot four-component reaction of aldehyde, amine, nitroalkane and 1,3-diketone using silica gel supported polyphosphoric acid (PPA–SiO2) under microw...

Following our previous report on a novel class of C4 symmetric porphyrazines bearing 2,5-dimethylpyrrolyl and methyl(3-pyridylmethyl)amino groups in the periphery, here we report the synthesis and characterization of unsymmetrical porphyrazines with peripheral 2,5-di(2-thienyl)pyrrolyl and dimet...

Publisher SummaryThis chapter deals with the acridine and phenanthridine systems, and a number of less well studied mono-aza-polybenzenoid structures. The main current scientific interest in these compounds lies in their carcinogenicity. Their biological activity and that of the carcinogens and ...

The high-performance liquid chromatographic (HPLC) separation of enantiomers of oxide and hydroxy derivatives of dibenz[a,j]acridine and 7-methylbenz[c]acridine was investigated on a chiral stationary phase chromatography column using commercially available columns. In most cases either poor or ...

Metabolism of the proximate carcinogen trans-3,4-dihydroxy-3,4dihydrodibenz[c,h]acridine has been examined with rat liver enzymes. The dihydrodiol is metabolized at a rate of 2.4 nmol/nmol of cytochrome P450 1A1/min with microsomes from 3-methylcholanthrene-treated rats, a rate more than 10-fold...

Publisher SummaryThe chapter discusses the amino acid esters of the ribonucleic acid (RNA), nucleosides, and related compounds. In this chapter, the literature on the chemistry of the amino acid esters of RNA, nucleotides, and nucleosides is surveyed. The related compounds includes: (i) compound...

Puerariae Lobatae Radix (PLR) exerts cyto-protective effect against oxidative stress due to its high isoflavonoid content. In this study, the ultrasonic-assisted extraction condition for the maximum recovery of isoflavonoids with high cyto-protective effect was optimised by response surface meth...