NEW HETEROCYCLIC SYSTEM SYNTHESIS VI． THE CYCLOADDITION DERIVATIVES OF 1，5－BENZOTHIAZEPINE AND 1，5－BENZODIAZEPINE

Dihydro-1H-1, 5-benzodiazepines and 1-benzoy1-2, 3-dihydro-1H-1H-1,5-benzodiazepines react with .α-carbonylkelenes, generated from 2-diazo-1,3-diphenyl-1,3-propandione or 2-diazo-1-phenyl-1,3-butandione by heating, to give 4a,5, 6, 12-letralydro- 1H,7H-1,3-oxazino[3,2-d][1,5]-benzodiazepine-1-ones,a new ring system. 2, 3-Dihydro-1H-1,5-benzodiazepines also afford,dducts of H-N bond,with a carbonylketenes, 2-aryt-1-(2-benzoyl-phenylacelyl)-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepines. Addition of henzonitrile N-phenylimine,yielde in situ from the N-phenyl benzenecarbohydrazic chloride,to 2, 4-diaryl-2, 3-dihydro-1,5-benzothiazepines and 1H-1,5-benzodiazepine gave 3a, 5-diaryl-1, 3-diphenyl-3a, 4, 5, 11 tetralydro-3H-1, 2, 4-triazolo [4, 3-d][1. 5]benzothiazepine and 3H,6H-1, 2, 4 triazolo[4, 3-d][1, 5] benzodiazpine, respectively.

NEW HETEROCYCLIC SYSTEM SYNTHESIS IV.4a, 5,6, 12-TETRAHYDRO-1H-1,3-OXAZ1NO [3,2-d][1,5]-BENZOTHIAZEPINE-1-ONE

Addition of a-carbonylketenes, generated from 2-diazo-1, 3-diaryl-1, 3-propandione or 2-diazo-1-phenyl-1,3-butandione by heating, to 2,4-diaryl-2,3-dihydro-[1,5]-benzothiazepines gave 2,3-disubstituted-4a, 6-diaryl-4a,5,6,12-telrahydro-1H-1, 3-oxazino[3,2d][1,5]-benzothiazepine-l-ones, a new ring system.

DESIGN，SYNTHESIS AND ACTIVITIES OF ANALOGS AND SEGMENTS OF THE PAPAVER SOMNIFERUM POLLEN PEPTIDE PSPP2~1

Four analogs and three segments of the Papaver somniferum pollen peptide 2 (PSPP2)were desiged and synthesized by using Merrifield solid phase peptide synthesis method. Their antitumour activities were detrminde by the tetrazolium salt MTT (3-(4,5-dimethylthiazol-2-yl)-2,5diphenyl tetraolium bromide) method and the relationship of tructure -activity was discussed.

Prediction, Synthesis and Antigenicity of the Antigenic Peptides of 26kDa Glutathione S-Transferasc of Schistosoma Japonicum (Sj26)

Six antigenic peptides of 26 kDa glutathione S-transferase of Schistosoma japonicum(Sj26) have been predicted according to their hydrophilicity, flexibility. accessibility. chargedistribution and β -turn in the secondary structure by the determination of its primary structure andsynthesized by solid phase method. All of them showed antigenicity with anti-schistosomajaponicum immunoglobulin polyclonal antibody, anti-Sj-lgG PcAb by Dot-ELISA. Three of themshowed good antigenicity. They would serve as candidates of synthetic anti-schistosomal vaccine.

Mapping the Antigenic Peptides of Sm26/2 in Glutathione S-Transferases of Schistosoma Mansoni

Six antigenic peptides of Sm26/2 glutathione S-transferase of schistosoma mansoni have been predicted according to their hydrophilicity, flexibility, accessibility, charge distribution and beta-turn in the secondary structure by the determination of its primary structure, and synthesized by solid phase method. Two of them showed good antigenicity by Dot-ELISA. They would be candidate peptides of synthetic anti-schistosomal vaccine.

A New Rearrangement Reaction of 2-Phenyl Substituted Benzothiazepine with Ethoxycarbonyl Carbene─Mechanism of the Reaction and Structure of the Product

2,3-Dihydro-2-phenyl-4-(4-methoxyphenyl)-1, 5-benzothiazepine reacts with ethoxycarbonyl carbene to give an unexpected compound 2,3-disubstituted-4H-1,4-benzothiazine Ⅲ. It was found to be a new rearrangement reaction and the structure of the product was confirmed by IR, NMR, MS.

Synthesis,Structure and Antitumor Activities of Tridccapeptide PSPP3 from Papaver Somniferum Pollen

Five analogs and five segments of the Papavor Somniferum pollen tridecapeptidePSPP3 were designed and synthesized by using solid-phase peptide synthesis method. Theirinhibitive activities to human liver tumor cell Bel-7402 were assayed by MTT method and theirsecondary structures in solution were determined by CD spectra. The relationship of the structureand activity was discussed.

DESIGN AND SYNTHESIS OF ANALOGS OF THE SCHISTOSOMA MANSONI P28 ANTIGENIC PEPTIDEP141

Four analogs of the Schistosoma mansoni P28 antigenic peptide P141 were designed according to the similarity in the structure of the amino acid residues and Chou-Fasman's secondary structurally conformational parameters P alpha, P beta and Pt values, also according to the hydrophilicity of the amino acid residues. They were synthesized by using Merrifield solid phase peptide synthesis method. ELISA experiments showed their antigenicity.

The transcription factor NAC102 confers cadmium tolerance by regulating WAKL11 expression and cell wall pectin metabolism in Arabidopsis

Cadmium(Cd) toxicity severely limits plant growth and development. Moreover, Cd accumulation in vegetables, fruits, and food crops poses health risks to animals and humans. Although the root cell wall has been implicated in Cd stress in plants, whether Cd binding by cell wall polysaccharides contributes to tolerance remains controversial, and the mechanism underlying transcriptional regulation of cell wall polysaccharide biosynthesis in response to Cd stress is unknown. Here, we functionally characterized an Arabidopsis thaliana NAC-type transcription factor, NAC102, revealing its role in Cd stress responses. Cd stress rapidly induced accumulation of NAC102.1, the major transcript encoding functional NAC102, especially in the root apex. Compared to wild type(WT) plants, a nac102 mutant exhibited enhanced Cd sensitivity, whereas NAC102.1-overexpressing plants displayed the opposite phenotype. Furthermore, NAC102 localizes to the nucleus, binds directly to the promoter of WALL-ASSOCIATED KINASE-LIKE PROTEIN11(WAKL11), and induces transcription, thereby facilitating pectin degradation and decreasing Cd binding by pectin. Moreover, WAKL11 overexpression restored Cd tolerance in nac102mutants to the WT levels, which was correlated with a lower pectin content and lower levels of pectin-bound Cd. Taken together, our work shows that the NAC102-WAKL11 module regulates cell wall pectin metabolism and Cd binding, thus conferring Cd tolerance in Arabidopsis.