This work reports the synthesis of novel 1,4,3,5-oxathiadiazepanes 4,4-dioxides from the reaction of N'-benzyl-N-(2-hydroxyethyl)-sarcosine or proline sulfamide with aromatic aldehydes under acid catalysis. To prepare the starting materials N-Boc-sulfamide derivatives of sarcosine or proline were alkylated with benzyl alcohol under Mitsunobu reaction conditions, the Boc group was removed chemos...

Mg-mediated addition of bromoform to electron deficient imines such as N-sulfonylimines affords α-tribromomethylated N-sulfonylamines in good to excellent yields. The procedure could be further simplified by transforming the imine precursors, α-sulfonyl-N-tosyl- and Boc-amines, in one pot to the corresponding α-tribromomethyl derivatives. Facile removal of the Boc protecting group in nearly qua...

In this paper, an analysis of a new synchronization technique for Binary Offset Carrier (BOC) modulated signals will be presented. Goal of the proposed method is to improve the synchronization performances by reducing the synchronization errors due to the characteristic BOC cross-correlation function. The synchronization is generally based on the envelope of the cross-correlation between the re...

The choice is yours: a highly stereoselective synthesis of α-alkyl-α-hydroxy-β-amino esters is accomplished through a tandem Wittig-rearrangement/Mannich reaction sequence. Transformations of N-benzyl or N-Boc imines proceed with high selectivity for formation of syn-amino alcohol derivatives, whereas N-Boc-2-(phenylsulfonyl)amines generate anti-amino alcohol products. Auxiliary cleavage (trans...

Residue based control of specific helical folding is explored in hybrid peptide oligomers consisting of alternating L-Ala and cis-beta-furanoid sugar amino acid (FSAA) residues as building blocks; two series of these hybrid oligomers are designed, synthesized and extensively characterized by using NMR, CD, FT-IR and MD simulation studies; results show the co-existence of left-handed 11- and 14/...

A series of new 1-aryl-4-(biarylmethylene)piperazines has been synthesized. These ligands are structurally related to SLV-313, a potential atypical antipsychotic having potent D2 receptor antagonist and 5-HT1A receptor agonist properties. Buchwald-Hartwig coupling reactions of 1-boc-piperazine with appropriate aryl halides and subsequent removal of the boc group rendered arylpiperazines. The re...

New coumarin-based chiral thiourea sensor 1 was found to be an enantioselective fluorescent chemosensor for N-Boc-protected proline. The chiral sensor shows lower background fluorescence, and higher fluorescence enhancement with 18 nm blue shifts. Job plot analysis result indicates that sensor 1 can form a 1 : 1 stoichiometric complex and it could be used as a fluorescence sensor for the determ...

The title mol-ecule, C(20)H(31)NO(8), has pseudo-C2 symmetry about the C-N bond, with the bis-(tert-butoxy-carbon-yl)amino group twisted from the benzene ring plane by ca 60° and the bulky tert-butoxy-carbonyl (Boc) groups are orientated away from the substituted aniline group. As part of an anti-bacterial drug discovery programme furnishing analogues of platensimycin, we unexpectedly synthesiz...

A simple, efficient, and eco-friendly protocol for the N-Boc protection of the amine moiety in a variety of compounds with di-tert-butyl dicarbonate under water-acetone catalyst-free conditions is described. The corresponding monocarbamate is obtained in excellent yields on short reaction times. No competitive side reactions such as isocyanate urea and O-Boc were observed. This method represent...

The chemoenzymatic synthesis of heparan sulfate tetrasaccharide (1) and hexasaccharide (2) with a fluorous tag attached at the reducing end is reported. The fluorous tert-butyl dicarbonate ((F)Boc) tag did not interfere with enzymatic recognition for both elongation and specific sulfation, and flash purification was performed by standard fluorous solid-phase extraction (FSPE). Based on an (F)Bo...