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11.
Transformations of N'-heteroaryl-N,N-dimethylformamidines 1 as a general method for the preparation of β-heteroarylamino-α,β-dehydro-α-amino acids, β-heteroarylamino-α-amino acid derivatives 5–9 , and dipeptides 10 , are described. 相似文献
12.
Noveron JC Lah MS Del Sesto RE Arif AM Miller JS Stang PJ 《Journal of the American Chemical Society》2002,124(23):6613-6625
We report the supramolecular chemistry of several metal complexes of N-(4-pyridyl)benzamide (NPBA) with the general formula [Ma(NPBA)2AbSc], where M = Co2+, Ni2+, Zn2+, Mn2+, Cu2+, Ag+; A = NO3-, OAc-; S = MeOH, H2O; a = 0, 1, 2; b = 0, 1, 2, 4; and c = 0, 2. NPBA contains structural features that can engage in three modes of intermolecular interactions: (1) metal-ligand coordination, (2) hydrogen bonding, and (3) pi-pi stacking. NPBA forms one-dimensional (1-D) chains governed by hydrogen bonding, but when reacted with metal ions, it generates a wide variety of supramolecular scaffolds that control the arrangement of periodic nanostructures and form 1- (2-4), 2- (5), or 3-D (6-10) solid-state networks of hydrogen bonding and pi-pi stacking interactions in the crystal. Isostructural 7-9 exhibit a 2-D hydrogen bonding network that promotes topotaxial growth of single crystals of their isostructural family and generates crystal composites with two (11) and three (12) different components. Furthermore, 7-9 can also form crystalline solid solutions (M,M')(NPBA)2(NO3)2(MeOH)2 (M, M' = Co2+, Ni2+, or Zn2+, 13-16), where mixtures of Co2+, Ni2+, and Zn2+ share the same crystal lattice in different proportions to allow the formation of materials with modulated magnetic moments. Finally, we report the effects that multidimensional noncovalent networks exert on the magnetic moments between 2 and 300 K of 1-D (4), 2-D (5), and 3-D (7, 8, 10, and 13-16) paramagnetic networks. 相似文献
13.
Methyl (E)-2-(acetylamino)-3-cyanoprop-2-enoate ( 2a ), and its 2-benzoyl analog 2b ere prepared from the corresponding methyl (Z)-2-(acylamino)-3-(dimethylamino)propenoates 1 Multifunctional compounds 2 are versatile synthons for preparation of polysubstituted heterocyclic systems such as pyrroles 4 , pyrimidines 5 and 6 , pyridazines 7 , pyrazoles 8 , 9 , and 11 , and isoxazoles 10 . 相似文献
14.
Lucija Jukić Urška Bratušek Marko Škof Jurij Svete Branko Stanovnik 《Chemistry of Heterocyclic Compounds》1996,32(11-12):1295-1299
A novel approach to the synthesis of 3-acylindolizines and the transformations of some acids into tryptophane analogues are described. Reaction of ethyl 2-pyridinylacetate and methyl 2-quinolinylacetate with N-trifluoroacetyl-5-bromo-4-oxonorvaline methylester led to N-trifluoroacetyl-3-(1-ethoxycarbonylindolizinyl-2) alanine methyl ester and N-trifluoroacetyl-3-(3-methoxycarbonylpyrrolo [1,2-a]quinolinyl-2) alanine methyl ester, respectively. Treatment of ethyl 2-pyridinylacetate and 2-pyridinylacetonitrile, first with N,N-dimethylformamide dimethyl acetal (DMFDMA), followed by reaction with phenacyl bromide, gave the corresponding 3-benzoylindolizines, while the reaction of ethyl 2-pyridinylacetate and 2-pyridinylacetonitrile with DMFDMA, followed by treatment with (S)-N-trifluoroacetyl-5-bromo-4-oxonorvaline methyl ester, gave the corresponding N-trifluoroacetyl-4-oxo-4-(indolizinyl-3)homoalanine methyl esters. 相似文献
15.
Benjamin Prek Jure Bezenšek Marta Kasunič Uroš Grošelj Jurij Svete Branko Stanovnik 《Tetrahedron》2014
Herein a simple one-pot metal-free synthesis of alkyl-, aryl-, heteroaryl- and alkoxycarbonyl substituted 1,3-bis(dimethylamino)benzene derivatives is described. The products were prepared from the corresponding methyl ketones or compounds with an α-methylene group in regard to the carbonyl group, using N,N-dimethylacetamide dimethyl acetal (DMADMA) as the reagent. 相似文献
16.
Miha Drev Uroš Grošelj Špela Mevec Eva Pušavec Janja Štrekelj Amalija Golobič Georg Dahmann Branko Stanovnik Jurij Svete 《Tetrahedron》2014
The synthesis of 7-substituted pyrazolo[1,5-a]pyrimidine-3-carboxamides was studied. First, methyl 7-hydroxypyrazolo[1,5-a]pyrimidine-3-carboxylate (5) was prepared in three steps from methyl 5-amino-1H-pyrazole-4-carboxylate (3). Treatment of 5 with POCl3 gave the highly reactive 7-chloro derivative 10, which was reacted with amines, benzyl alcohol, and phenylboronic acid in the presence of Pd-catalyst to give the corresponding 7-substituted derivatives 11. Hydrolysis of the esters 5 and 11 followed by amidation gave the corresponding carboxamides 16a–h and 15. Regioselectivity of N-alkylation of 7-hydroxypyrazolo[1,5-a]pyrimidine-3-carboxylic acid derivatives 5 and 16 was tunable by the carboxy function. Alkylation of the secondary amides 16a–f furnished the 1-alkyl derivatives 17a–f, whereas the ester 5 and the tertiary amides 16g,h gave the 4-alkyl derivatives 14a–d and 16m,n, selectively. 相似文献
17.
18.
Zajc B Grahek R Kocijan A Lakshman MK Kosmrlj J Lah J 《The Journal of organic chemistry》2003,68(8):3291-3294
The enantiomeric resolution and the elution order of (+/-)-trans-7,8-dihydrodiols of benzo[a]pyrene and its 6-fluoro and 6-bromo derivatives were analyzed on three polysaccharide-based columns: Daicel Chiralcel CA-I (cellulose triacetate), OF, and OG [cellulose tris(4-chloro- and 4-methylphenylcarbamate)]. For comparison, the separation of (+/-)-1,1'-bi-2-naphthol was evaluated on the OG and OF columns. Possibly similar interactions of (S)-1,1'-bi-2-naphthol and (7S,8S)-isomers of 6-halo-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene with the chiral sorbent are suggested. 相似文献
19.
20.
Damjana Miheli
Renata Jake Jurij Svete Branko Stanovnik Simona Goli Grdadolnik 《Journal of heterocyclic chemistry》2001,38(6):1307-1312
(S)‐5‐Benzoyloxymethyl‐3‐[(E)‐(dimethylamino)methylidene]tetrahydrofuran‐2‐one (6), prepared in 5 steps from L‐glutamic acid (1), was used as precursor in a one step ‘ring switching’ synthesis of (S)‐2‐hydroxy‐3‐heteroaryl‐l‐propyl benzoates 13‐18, 23, 24. In the reaction of 6 with 2‐aminopyridine (21) and 2‐amino‐4,6‐dimethylpyrimidine (22) the corresponding dimethylamine substitution products (25, 26) were obtained. 相似文献