A three step enantio-enriched protocol to the iridolactone core of brasoside is reported. Stereo-control reduction of [(1S,2R,3S)-3-methyl-2(nitromethyl)-5-oxocyclopentyl]acetic acid 3 afforded (3aR,4S,5R,6aS)-5-methyl-4-(nitromethyl)-hexahydrocyclopenta[b]furan-2-one 4. A further formylation strategy on the AB-ring system 4 afforded the enol ester 5, followed by Nef reaction of the nitoo functionality and acid quenching to the desired tricyclic lactone 11. Chiral -keto-acid 3 was used, since this precursor contains three functional groups: ketone, carboxylic acid, nitromethyl; it is also available in bulk as a pure enantiomer at low price.

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A successful two-step annelation protocol of diesters and methyl bro moacetate with 2-chlorocyclopentanone derivatives was efficiently pursued, wh ich gave suitably substituted bicyclic lactones in high overall yields and with co mplete streoselectivity med iated by K-Selectride and Wilkinsons catalyst, is reported. As part of a program aimed at rapid synthesis of bicyclic lactones which inherently occurs in many active natural p roducts, this paper has shown a novel and rare methods for the synthesis of these important compounds based on alkylation of cyclopentanone derivatives and further demonstrate efficient reduction protocol of these compounds to the bicyclci lactones

There is an increasing attempt in biodiesel production (fatty acid methyl ester) because of the depleting fossil fuel resources as well as the similarity in properties when compared to those of diesel fuels. Engines set off on biodiesel have lower emissions of carbon monoxide, unburned hydrocarbons, and air toxics than engines runned on petroleum-based diesel fuel. We reported the optimization of Coconut oil methyl esters production via methyl ester from black oil/castor seed oils admixture under various operating conditions. The optimum yield, temperature, catalyst concentration and reaction time were found to be 93%, 60°C, 1.0% (wt of crude oil admixture) and 60 minutes respectively. Many fuel properties (viscosity, specific gravity and flash point) as measured according to standard methods, also found to conform to international standard.