The asymmetric synthesis of the highly functionalized (3R,5R,6R)-3,6-diamino-5-hydroxyheptanoic acid, the key amino acid fragment of sperabillins B and D, was achieved by an asymmetric Michael addition of lithium (R)-(α-methylbenzyl)allylamide 10 to (E,E)-2,5-heptadienoate establishing the C-3 ...

The chemo- and enantioselective reduction of ethyl 4-chloroacetoacetate and the diastereoselective conjugate addition of enantiopure lithium N-benzyl-N-(α-methylbenzyl)amide to an α,β-unsaturated ester have been used as the key steps in the total asymmetric syntheses of (+)-negamycin (in 13 s...

Structure and bonding analysis of the FeO bonds in the model heme-imidazole and heme-thiolate complexes [(por)Fe(Im)(R)] (R = HC(O)O−, 1FeIm, R = H3CC(O)O−, 2FeIm, R = NO3−, 3FeIm) and [(por)Fe(SMe))(R)]− (R = HC(O)O−, 4FeSMe, R = H3CC(O)O−, 5FeSMe, R = NO3−, 6FeSMe) were investigated at the DFT...

Arsenic species, including arsenous acid, arsenic acid, methylarsonic acid, and dimethylarsinic acid, were determined using HPLC–ICPMS. The species were separated with a Discovery HS F5 column and a simple, volatile, and isocratic mobile phase of 0.1% (v/v) formic acid and 1% (v/v) methanol. Th...

X-ray diffraction studies show that peptides Boc-Leu-Aib-m-ABA-OMe (I) (Aib, α-aminoisobutyric acid; m-ABA, meta-aminobenzoic acid) and Boc-Phe-Aib-m-ABA-OMe (II) adopt a type-II β-turn conformation, solely stabilized by co-operative steric interactions amongst the amino acid residues. This ty...

The exploitation of peptides in the development of smart nanomaterials is gaining increasing attention in the last few years. Amino acids are indeed able to drive the self-assembly and the self-organization at the molecular level. By using non-standard amino acids, it is possible to expand the s...

The development of synthetic receptors is a classic field in supramolecular chemistry. Many of the known receptors comprise building blocks that have no direct counterpart in Nature. In addition, there exists another class of receptors that either contain amino acids as subunits or are even full...

Strained unusual amino acid derived tetrapeptides were synthesized as mimics of GLYX-13, a clinical candidate for neuroprotective and anti-depressant properties, were studied. The synthesized compounds were screened for neurite growth and anti-depressant properties in vitro and in vivo respectiv...

Robust oligopeptides that mimic natural ion channels are attractive for use as molecular switches or model systems to study ion transport. Herein, we report octapeptides derived from aminobenzoic acid and l/d amino acids. Two of the alanine containing peptides were found to be most active and th...

We report an efficient and practical synthetic route to various properly-protected erythreo-β-OH-Asp compounds, which are key β-branched α-amino acid units in coralmycin A and other peptide natural products. Fmoc and cyclic ketal-protected erythreo-β-OH-Asp 7 is prepared from cheap chiral pr...

Several methods for polymerizing 4-methyl-2-oxetanone (β-butyrolactone, BL) were developed allowing the controlled synthesis of polymers with molar masses up to 100 kDa. Although new catalytic systems have been described for the living anionic polymerization of BL, no detailed studies have been...

The polymerization of n-butyraldehyde, via a metal-free organocatalytic anionic polymerization method was successfully conducted with the phosphazene bases P2-t-Bu and P4-t-Bu. Well-defined poly(n-butyraldehdye) (PBA), with predictable molar masses and low molar mass dispersities (Ð) were access...

Hydroamination and hydrothiolation are the most efficient and completely atom-economical process to construct important enamine and vinyl sulfide intermediates in pharmaceutical and organic chemistry. The cyclic trimeric phosphazene base (CTPB) showed great catalytic activity for the anti-Markov...

We demonstrated that the dimeric 1-tert-butyl-2,2,4,4,4-pentakis(dimethylamino)-2Λ5, 4Λ5-catenadi(phosphazene) supported on polystyrene (PS-t-BuP2) was an efficient and recyclable catalyst for the ring-opening polymerization (ROP) of δ-valerolactone (δ-VL). The heterogeneous catalyst PS-t-Bu...

Oxaliplatin is a promising antitumor drug, but its effectiveness is limited by its side effects in vivo. In this study, we introduced an Oxaliplatin prodrug (Oxa(IV)) self-controlled release strategy, in which Oxa(IV) is encapsulated by TPGS functionalized mesoporous silica nanoparticles (MSNs),...

Pt(IV) prodrugs, with two additional coordination sites in contrast to Pt(II) drugs, have been actively studied nowadays, for they can perform well in enhancing the accumulation and retention of the corresponding Pt(II) drugs in cancer cells. Our designed Pt(II) drug, DN604, was recently found t...

Due to their high NIR-optical absorption and high specific surface area, graphene oxide and graphene oxide-based nanocomposites have great potential in both drug delivery and photothermal therapy. In the work reported herein we successfully integrate a Pt(IV) complex (c,c,t-[Pt(NH3)2Cl2(OH)2]), ...

Platinum(IV) pro-drugs are an important class of molecules that might improve the pharmacological properties of the platinum(II) anticancer agents that are currently used in the clinic. Their axial ligands that are detached during cellular activation by reductive elimination can be used to confe...

Platinum-based complexes like cisplatin and oxaliplatin are well known the mainstay of chemotherapy regimens on clinic. Wogonin, a natural product that possesses wide biological activities, is now in phase I clinical test as an anticancer agent in China. Herein reported are a series of novel Pt(...

Unprotected nucleosides 1 were thiophosphorylated with thlophosphoryl chloride in trlalkyl phosphates and directly cycllzed by alkali hydroxide in aqueous acetonftrile to give the diaslereomers 3 and 4 of nucleoslde - 3', 5'- cyclic phosphorothioates in good yields.