The addition of 4 eq of chloral to osmundalactone (4S,5R)-4 gave quantitative formation of the hemiacetal derivative (4S,5R)-8, which was treated with methane sulfonic acid to afford the intramolecular Micheal addition product (+)-(3S,4S,5R)-9 possessing a 3,4-cis-dihydroxy-δ-lactone in 78% overall yield from (4S,5R)-4. The obtained (+)-(3S,4S,5R)-9 was subsequently converted to methyl D-digito...

The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ≈42% yield over six steps start...

Two new carbapenem antibiotics, carpetimycins C and D have been isolated from the culture broth of Streptomyces p. KC-6643, which produced carpetimycins A and B. The structures of carpetimycins C and D have been determined to be (5R,6R)-3-[2-acetamidoethyl(R)-sulfinyl]-6-(1-hydroxy-l-methylethyl)-7-oxo-l-azabicyclo[3.2.0]hept-2-ene-2-carboxylic a id and (5R,6R)-3-[2-acetamidoethyl-(R)-sulfinyl]...

Cyanine dyes attached to DNA via a rigid linker show useful fluorescence and FRET properties without altering the stability of duplex DNA.

In this paper, 2,3,3-trimethyl-3H-indolin was synthesized by phenylhydrazine and 3-methyl-2-butanone as raw materials in the acetic acid reacted with different nitrogenalkylating reagents. Semi mono-cyanine dye and semi dicyanine dye were prepared with the help of squaric acid diethyl ester. The spectral properties of the target products were checked. The results show that compared with symmetr...

(+)-Trans-(5R,6R)-5-bromo-6-ethoxy-5-ethyl-5,6-dihydro-2'-deoxyuridine [(5R,6R)-BEEDU], a potential brain-targeted prodrug of 5-ethyl-2'-deoxyuridine (EDU), was synthesized by the regiospecific addition of BrOEt to the 5,6-olefinic bond of EDU. (5R,6R)-BEEDU is more lipophilic (log P = 0.04) than EDU (log P = -1.09). In vitro incubation of (5R,6R)-BEEDU with rat whole blood and brain homogenate...

Genetic maps containing molecular markers are useful tools for the identification of genes underlying quantitative traits (QTLs). Three traits important for plant physiology, i.e. chlorophyll content, sensitivity to GA and sensitivity to ABA, were evaluated for 99 F2 families of the DS2 x RXL10 rye mapping population. The observed variation in the chlorophyll content in rye leaves was shown to ...

Supramolecular self-assembling cyanine and spermine binding to genomic DNA was a model for DNA-drug interactions during high throughput screening. Spermine competitively inhibited the self-assembly of cyanine upon DNA scaffolds as signaled by decreased fluorescence from the DNA-cyanine J-aggregate. The sequence of DNA exposure to cyanine or spermine was critical in determining the magnitude of ...