A facile synthesis of some substituted furopyrimidine derivatives

Some substituted furopyrimidine derivatives are prepared in high yield in 4 steps, starting from the reaction of furoin (1,2‐di(furan‐2‐yl)‐2‐hydroxyethanone) and malonitrile.     

Direct, facile synthesis of N-acyl-alpha-amino amides from alpha-keto esters and ammonia

N-Acyl-alpha-amino amides were prepared, without the necessity of chromatographic purification, in a single step by heating the corresponding alpha-keto ester in methanolic ammonia.     

Efficient synthesis and facile polymerization of some cyclic bisphenol o-phthalates

A series of new macrocyclic aromatic esters have been efficiently synthesized from o-phthaloyl dichloride and various bisphenols, and unambiguously characterized by a combination of GPC, MS(FAB), FTIR and NMR. These macrocyclic oligomers undergo facile ring-opening polymerization in the presence of anionic initiators to give high molecular weight polyarylates.     

The facile reduction of methoxyethoxymethyl esters with lithium triethylborohydride

The use of a methoxyethylmethyl (MEM) ester has been shown to facilitate the selective reduction of that ester function in the presence of other reduceable esters.     

The facile synthesis of 5-formylporphyrin

A facile synthetic route of 5-formylporphyrin(2) has been developed.Using pyrrole and pivaldehyde as the starting materials,2 was obtained through several facile reactions.The synthetic route is easy to perform and can be scaled up,which gives the compound a better application perspective.     

A facile one-pot synthesis of α-fluoro-α,β-unsaturated esters from alkoxycarbonylmethyltriphenylphosphonium bromides

A convenient one-pot synthesis of α-fluoro-α,β-unsaturated esters from ethoxy- and tert-butoxycarbonylmethyltriphenylphosphonium bromide was developed. The fluorinated phosphoranes, generated in situ from alkoxycarbonylmethyltriphenylphosphonium bromides and 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor^®), undergo a Wittig reaction with aldehydes to yield α-fluoro-α,β-unsaturated esters with (Z)-selectivity.     

Synthesis of some new five membered heterocycles,a facile synthesis of oxazolidinones

The synthesis and structural properties of two kinds of thiosemicarbazide derivatives ( 2a‐c and 3a‐c ) and one kind of semicarbazide derivatives ( 4a, 4b ) have been described. These compounds were synthesized by treating 2‐(4‐amino‐3‐alkyl‐5‐oxo‐4,5‐dihydro‐1H‐1,2,4‐triazol‐1‐yl)acetohydrazides ( 1a‐c ) with benzyl isothiocyanate, 3‐florophenyl isothiocyanate and benzylisocyanate, respectively. The synthesis of 4‐amino‐3‐alkyl‐1‐[(4‐alkyl‐5‐mercapto(or 5‐oxo)‐4H‐1,2,4‐triazol‐3‐yl)methyl]‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones ( 5a‐c, 6a‐c and 7 ) have been performed from the reaction with sodium hydroxide. On the other hand, the acidic treatment of compounds 2b, 3b and 4b has afforded 4‐amino‐3‐(4‐chlorobenzyl)‐1‐[(5‐alkylamino‐1,3,4‐thidazol(or 1,3,4‐oxazol)‐2‐yl)methyl]‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones ( 8, 9 and 10 ). The condensation of thiosemi(or semi)carbazide derivatives ( 2a‐c, 3c and 4b ) with 4‐chlorophenacylbromide have resulted in the formation of 2‐[4‐amino‐3‐alkyl‐5‐oxo‐4,5‐dihydro‐1H‐1,2,4‐triazol‐1‐yl]‐N′‐(3,4‐dialkyl‐1,3‐thiazol(or oxazol)‐2(3H)‐yliden]acetohydrazides ( 11a‐c, 12, 13 ), while their condensation with chloroacetic acid has produced 2‐[4‐amino‐3‐alkyl‐5‐oxo‐4,5‐dihydro‐1H‐1,2,4‐triazol‐1‐yl]‐N′‐[3‐(3‐alkyl)]‐4‐oxo‐1,3‐thiazolidin(or oxazolidin)‐2‐yliden}acetohydrazides ( 14, 15 and 16 ). The spectral data and elemental analyses have support the proposed structures.     

The facile solid-phase synthesis of cholesterol-based polyamine lipids

A facile solid-phase methodology for the production of cholesterol-based polyamines useful in mediating nucleic acid delivery for gene therapy is described. The methodology is compatible with a range of polyamines producing a library of lipids in excellent yields (>87%) and purity.     

Reactions of borinic esters with (1,1-dichloroalkyl)lithium. A facile synthesis of tertiary carbinols

The reaction of various borinic esters with (1,1-dichloroalkyl)lithium, LiCRCl₂ (R = phenyl, methyl), followed by the treatment of base and hydrogen peroxide is a facile route to tertiary carbinols.     

A facile synthesis of α-chloroboronic esters via the base induced reaction of α,α-dichloromethyl methyl ether with hindered borinic esters

Treatment of hindered borinic esters, R₂ BOR′; with an equimolar quantity of α,α-dichloromethyl methyl ether and lithium triethylcarboxide yields the α-chloroboronic esters, R₂ CHClB(OCH₃)OR′, in excellent yields. In cases where the steric requirements of R are not sufficient, the steric requirements of R′ can be increased to achieve the synthesis.     

A facile synthesis of cyclotriveratrylene

Cyclotriveratrylene (CTV) can be readily synthesized by chloromethylation or bromomethylation of dimethoxybenzene with halomethyloctyl ether in the presence of SnCl₄. The reaction provides the trimer exclusively and in high yield. Recrystallizations from benzene or CHCl₃ yielded the solvent inclusion complexes and did not remove other inclusion impurities. Flash chromatography on silica yielded the pure CTV.¹³C NMR shows only five signals and no impurities.     

A facile synthesis of N-sulfinylaldimines

A simple and efficient procedure for the synthesis of N-sulfinylaldimines (sulfinimines) from sulfinamides and aldehydes is described. The reaction was carried out in the presence of t-BuOK or NaOH. The method is applicable for the synthesis of optically active sulfinimines.     

A facile synthesis of muscimol

The psychoactive isoxazole muscimol $\text{10}$ has been synthesized in three steps from propargyl chloride.     

A facile synthesis of cyclononatripyrroles

A facile synthesis of a functionalized cyclononatripyrrole derivative is described. It involves the iodine-catalyzed cyclotrimerization of ethyl 3,3-dimethyl-5,7-dihydro[1,3]dioxepino[5,6-c]pyrrole-6-carboxylate in methanol. The product obtained in this way exists solely in the crown conformation typical of cyclononatripyrroles. However, in contrast to previously reported compounds of this class, it possesses three labile methoxymethyl arms that can be further functionalized under acidic conditions.     

A facile synthesis of cyanophenothiazines

A one-pot synthesis of 1, 3 and 4-cyanophenothiazines and a two-step approach to 2-cyanoisomer have been developed. The condensation of 2-aminobenzenethiol and 2,3 or 3,4-dihalogenobenzonitriles followed by Smiles rearrangement or by intramolecular aromatic substitution gave the desired ring systmes.     

A facile synthesis of ulicyclamide

Ulicyclamide (1), a cytotoxic cyclic peptide from a marine tunicate, has been efficiently synthesized by the solid-phase method using diethyl phosphorocyanidate for the coupling and trimethylsilyl triflate for the final deprotection.     

A facile synthesis of polyfoluoroalkyl-lactonization

2(-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.