Display options:
Normal
Show Abstracts
Compact
Displaying article 1-7
p. 516-520
Received: 10 November 2004 / Accepted: 10 March 2005 / Published: 13 May 2005
Show/Hide Abstract
| Download PDF Full-text (79 KB) Abstract: Benzene, halobenzenes and some deactivated arenes readily reacted inanhydrous NaIO4 /AcOH/Ac2 O/concd. H2 SO4 mixtures to afford, after quenching withexcess aqueous Na2 SO3 solution (a reducing agent), purified iodinated products in 27-88% yields. This novel method of aromatic iodination is simple, fairly effective andenvironmentally safe.
p. 521-533
Received: 13 September 2004; in revised form: 10 January 2005 / Accepted: 10 January 2005 / Published: 13 May 2005
Show/Hide Abstract
| Download PDF Full-text (348 KB) Abstract: Benzylidene acetone reacts with thiocyanates derived from secondary amines in a one-pot reaction to give 4-aminobicyclo[2.2.2]octan-2-ones. The reaction mixture was investigated for the presence of possible intermediates using GC-MS. These intermediates – diketones and enamines – were prepared and exposed to the same reaction conditions to examine the reaction mechanism. The reaction of ethyl styryl ketone with thiocyanates of secondary amines yielded cyclohexanone derivatives instead of the expected bicyclo- octanones. Their structures were established by means of a single crystal structure analysis.
p. 534-544
Received: 21 September 2004; in revised form: 20 January 2005 / Accepted: 21 January 2005 / Published: 13 May 2005
Show/Hide Abstract
| Download PDF Full-text (230 KB) Abstract: Methoprene, an insect growth regulator, was complexed with β-cyclodextrin, yielding a stable inclusion complex. TGA, X-ray powder diffraction and conformational analysis have been used to confirm the nature of this inclusion complex. The interaction between methoprene and β-cyclodextrin was investigated by means of Molecular Mechanics. The results account for the formation of a 1:1 inclusion complex stabilised by Van der Waals forces and hydrogen bonds. The [methoprene–β-cyclodextrin] complex included in smoke generating formulations and protected from thermal decomposition by the foaming agent azodicarbonamide was shown to be stable enough to release methoprene in fumes with good yields. The improved stabilty of the methoprene complex showed a correlation with increased biological activity against Musca domestica.
p. 545-551
Received: 31 January 2004 / Accepted: 5 February 2005 / Published: 13 May 2005
Show/Hide Abstract
| Download PDF Full-text (54 KB) Abstract: We report herein the synthesis of substituted 2-(6-nitrobenzo[1,3]dioxol-5-yl)-1- aryl ethanols and 2-(6-nitrobenzo[1,3]dioxol-5-yl)-propionic acid ethyl esters from the reaction of 5-chloromethyl-6-nitrobenzo[1,3]dioxole with various aromatic carbonyl and α- carbonyl ester derivatives using the tetrakis(dimethylamino)ethylene (TDAE) methodology.
p. 552-558
Received: 17 August 2004; in revised form: 24 January 2005 / Accepted: 28 January 2005 / Published: 31 March 2005
Show/Hide Abstract
| Download PDF Full-text (101 KB) Abstract: Natural monoglycerides of cinnamic, ferulic and p-coumaric acids were synthesized in good to high overall yields from isopropylidene glycerol via the Mitsunobu reaction and further deprotection of the corresponding acetonides with Amberlyst 15. The method avoids the need of protection of the phenolic hydroxyls. During the Mitsunobu esterifications a strong influence of the acid strength on the efficacy and outcome of the reaction was observed.
p. 559-571
Received: 17 July 2004; in revised form: 28 December 2004 / Accepted: 4 January 2005 / Published: 31 March 2005
Show/Hide Abstract
| Download PDF Full-text (317 KB) Abstract: The 1H-pyrazole-3-carboxylic acid 2 was converted in good yield (69%) into the corresponding 1H-pyrazole-3-carboxamide 5 via reaction of the acid chloride 3 with 2,3- diaminopyridine (4). A different product, the 3H-imidazo[4,5-b] pyridine derivative 6, was formed from the reaction of 3 with 4 and base in benzene for 5 hours. The structures of the synthesized compounds were determined spectroscopically. The mechanism of the reaction between 3 and 4 was examined theoretically.
p. 572-582
Received: 1 July 2004; in revised form: 26 February 2005 / Accepted: 1 March 2005 / Published: 25 May 2005
Show/Hide Abstract
| Download PDF Full-text (268 KB) Abstract: Dehydroepiandrosterone (DHEA) reacted with m-chloroperoxybenzoic acid(m-CPBA) to form 3β-hydroxy-5α,6α-epoxyandrostan-17-one (1), but it did not reactwith 30% H2 O2 . 1,4,6-Androstatrien-3,17-dione (2) was obtained from DHEA and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in dioxane. Compound 2 was reacted with 30%H2 O2 and 5% NaOH in methanol to give 1α,2α-epoxy-4,6-androstadien-3,17-dione (3),which was stereoselectively reduced with NaBH4 to form 1α,2α-epoxy-4,6-androstadien-3β,17β-diol (7) and reacted with Li metal in absolute ethanol-tetrahydrofuran mixture togive 2-ethoxy-1,4,6-androstatrien-3,17-dione (8). Compound 2 was also epoxidized withm-CPBA in dichloromethane to afford 6α,7α-epoxy-1,4-androstadien-3,17-dione (4),which was reacted with NaBH4 to synthesize 6α,7α-epoxy-4-androsten-3β,17β-diol (9).Compound 4 was reduced with Li metal in absolute ethanol-tetrahydrofuran mixture toform 7β-ethoxy-6α-hydroxy-1,4-androstadien-3,17-dione (10). Compound 2 was reducedwith NaBH4 in absolute ethanol to form 4,6-androstadien-3β,17β-diol (5), which wasreacted with 30% H2 O2 to give the original compound, but which reacted with m-CPBAto give 4β,5β-epoxy-6-androsten-3β,17β-diol (6).
Displaying article 1-7
Plain Text
BibTeX
BibTeX (without abstracts)
Endnote
Endnote (without abstracts)
Tab-delimited
PubMed XML
DOAJ XML
AGRIS XML
to open them.