60960-88-5

Flavin-dependent "ene"-reductases can generate stabilized alkyl radicals when irradiated with visible light; however, they are not known to form unstabilized radicals. Here, we report an enantioselective radical cyclization using alkyl iodides as precursors to unstabilized nucleophilic radicals. Evidence suggests this species is accessed by photoexcitation of a charge-transfer complex that forms between flavin and substrate within the protein active site. Stereoselective delivery of a hydrogen atom from the flavin semiquinone to the prochiral radical formed after cyclization provides high levels of enantioselectivity across a variety of substrates. Overall, this transformation demonstrates that photoenzymatic catalysis can address long-standing selectivity challenges in the radical literature.

Both E- and Z-N′-alkenyl urea derivatives of imidazolidinones may be formed selectively from enantiopure α-amino acids. Generation of their enolate derivatives in the presence of K+ and [18]crown-6 induces intramolecular migration of the alkeny

A rapid and diastereoselective method was developed for the [2,3]-sigmatropic rearrangement of N-Allyl ammonium ylides, affording products in up to 95percent isolated yields and up to 97:3 dr; most of the desired products were formed within 1 minute. For

The invention provides a method for preparing naftifine hydrochloride. The finished naftifine hydrochloride is obtained through subjecting relatively-cheap cinnamyl alcohol, which serves as a raw material, to chlorinating-reagent chlorinating, methyl-amination and 1-chloromethyl naphthalene substitution sequentially, and finally, carrying out acidification salt-forming and crystallization refining. According to the method provided by the invention, all intermediates in first three steps of reactions are subjected to a reaction without purification, process flows are continuous and non-intermittent, the operation is simplified, the yield and production efficiency of the product are increased, and meanwhile, the purity of the product is ensured, so that the method is applicable to industrialization; and meanwhile, the method has the advantages of simple reaction conditions, low cost and environment-friendliness.

Functionalized imidazolidin-2-one were prepared by using an iron-catalyzed alkene oxyamination reaction. Hy-droxylamine derivatives were used in this atom-economical process, and the addition of an external oxidant was not required. The conditions developed were shown to be efficient for mono-, di-, and trisubstituted double bonds, and a large scope of diamino alcohol precursors were delivered in good yields with good diastereoselectivities. The mechanistic pathway was studied and appears to involve both a fused aziridine and a carbocationic species.

A new strategy has been established for the [2,3]-sigmatropic rearrangement of quaternary allylic ammonium ylides via in situ activation of tertiary allylic amines with arynes under mild conditions. Using 2-(trimethylsilyl)aryl triflates as aryne precurso

A new approach to the synthesis of substituted 5-membered cyclic guanidines is described. Palladium-catalyzed alkene carboamination reactions between acyclic N-allyl guanidines and aryl or alkenyl halides provide these products in good yield. This method

Positive water effect: A catalyst composed of [Pd2(dba) 3] (dba=dibenzylideneacetone) and (S)-Siphos-PE is effective for the enantioselective coupling of N-allyl ureas with aryl bromides to afford 4-substituted imidazolidin-2-ones. Added water leads to significantly improved enantioselectivities with electron-poor aryl halide substrates. It is suggested that the C-C bond-forming reductive elimination is the enantiodetermining step in these reactions. Copyright

The present invention relates to amine derivatives represented by formula (1) or salts thereof. R3represents C1-C3 alkyl, hydroxylated C1-C5 alkyl, C1-C5 acyl; C2-C5 alkenyl, or a halogen atom; and k, l, and m are each an integer of 1 to 4.) Exhibiting excellent antifungal effect, these compounds are highly useful as antifungal agents, antifungal compositions, drugs, etc.

-

Novel amine derivatives having an excellent antimycotic effect represented by general formula (1) below and salts thereof are provided. [in the formula (1, R1represents a C1-5alkyl group which may be halogenated, R2represents 4-(1,1-dimethylalkyl)benzyl group, 4-(1-methyl-phenylethyl)benzyl group, 1-or 2-naphthylmethyl group, or a hydrocarbon group having 3,3-dimethyl-1-butynyl group or a phenyl group at its terminal and 1 to 3 double bonds; R3represents oxygen atom or a methylene group which may be substituted by a C1-4alkyl group; and R4represents 1-or 2 naphthyl group or a phenyl group which may be substituted.

The photophysical and photochemical behavior of a series of secondary and tertiary ω-(β-styryl)aminoalkanes with one to five methylenes separating the styryl and amino groups has been investigated and compared to the intermolecular reactions of 1-phenylpropene with secondary and tertiary amines. The tertiary styrylamines form fluorescent intramolecular exciplexes, but fail to undergo intramolecular addition reactions. Both the rate constant for exciplex formation and the stability of the exciplex are dependent upon the length of the polymethylene chain connecting the chromophores. The failure of the tertiary amine exciplexes to undergo intramolecular addition is attributed to an unfavorable exciplex geometry for α-C-H transfer to the styrene double bond. While the secondary styrylamines do not form fluorescent exciplexes, the dependence of the styrene singlet lifetime upon the polymethylene chain length is similar to that for the tertiary styrylamines. Intramolecular N-H addition to the styrene double bond results in the formation of two regioisomeric (α-phenyl and α-benzyl) cyclic amines of different ring size. The regioisomer of larger ring size is favored except in the case in which four methylenes separate the chromophores. The effects of polymethylene chain length, solvent polarity, temperature, and the bulk of the N-alkyl group upon product yields and ratios are discussed in terms of a mechanism involving singlet exciplex and biradical intermediates.

Free radical initiation of N-allyl-2-aminothiols 1-6 bearing substituents on the double bond give a mixture of thiazolidines and thiomorpholines.The more substituted the double bond the higher is the ratio of thiomorpholine/thiazolidine.To rationalize the

Reaction of ylides from 3-9 with benzaldehyde show that carboxylate and oxido functionalities proximate to the ylide center promote anomalously high E stereoselectivity in alkene formation.Through the use of α-deuterated ylides 12-14, an internal "trans-selective Wittig" mechanism was ruled out as a principal source of exaggerated E alkene production.