Assessment of per se performance, combining ability, hybrid vigour and reaction to major diseases in pigeonpea [Cajanus cajan (L.) Millsp.]

An experiment was carried out using seven cytoplasmic-genetic male sterile (CGMS) lines as females and seven diversified testers as males in a line × tester design. The analysis of variance for parents, females x males, hybrids and parents vs hybrids showed significant differences for almost all characters studied indicating the presence of sufficient variability among parents. Analysis of variance for combining ability revealed that mean squares due to females and line x tester interaction were significant for most of the characters. Thereby it is suggested that the variation in hybrids in respect of seed yield may be strongly influenced by the female lines. Analysis of variance revealed that the ratio of variance due to GCA to SCA was less than unity for all the characters indicating that these traits may be under the influence of non additive gene action and these characters are more likely to be improved through heterosis breeding. The gca effects of parents revealed that ICPA-2043, ICPA-2047, ICPA-2078, AKT-9913, BDN-2 and GRG-811 were good general combiners for seed yield and it’s direct compo-nents. The top three crosses exhibiting high specific combing ability effects along with their Per se performance, standard heterosis and gca status of the parents indicated that the cross combinations ICPA-2092 x GRG-811, ICPA-2043 x ICP-7035 and ICPA-2047 x RVKP-261 were good specific combiners for seed yield. These parental combinations are being used for exploitation of hybrid vigour. The good general combiners (ICPA-2043, ICPA-2047, ICPA-2078, AKT-9913, BDN-2 and GRG-811) and promising crosses viz. ICPA-2047 x GRG-811 and ICPA-2047 x BDN-2 were resistant for SMD and Fusarium wilt diseases, having high mean performance, positive sca effects for seed yield were identified from the present investigation and these may be useful in future breeding program

2,4,5-Trichlorophenyl-(9<i>H</i>-fluoren-9-ylmethoxycarbonylamino)methylcarbamates: Synthesis, isolation, characterization and utility in the synthesis of dipeptidyl ureas

1046-1053An efficient synthesis of 2,4,5-trichlorophenyl-(9H-fluoren-9-ylmethoxycarbonylamino)methylcarbamates employing isocyanates derived from several Fmoc-amino acids has been described. All the carbamates made have been obtained as crystalline solids and are fully characterized by IR, 1H NMR, 13C NMR and mass spectrometry. They have been used as building blocks for the synthesis of several dipeptidyl urea esters. The coupling of carbamates with N,O-bis[trimethyl­silyl]amino acids resulted in Fmoc-protected dipeptide urea acids in good yield as well as purity. All the dipeptidyl urea esters and acids made have been well characterized

Homologation of <i>α</i>-amino acids to <i>β</i>-amino acids: 9-Fluorenylmethyl chloroformate as a carboxyl group activating agent for the synthesis of <i>N^α-</i> protected aminoacyldiazomethanes

2152-2158An efficient and stereospecific homologation of urethane-protected α-amino acids to β-amino acids by Arndt-Eistert approach using an equimolar mixture of Fmoc-/Boc-/Z-α-amino acid and 9-fluorenylmethyl chloroformate for the acylation of diazomethane synthesizing the key intermediates Fmoc-/Boc-/Z-α-aminoacyldiazo-methanes as crystalline solids is described. They are then converted to the corresponding,β-amino acids using silver benzoate/1,4-dioxane-water under microwave irradiation. All the protected β-amino acids prepared have been obtained in good yield as well as purity

Ultrasound accelerated synthesis of proteinogenic and <img src='/image/spc_char/alpha.gif' border=0>,<img src='/image/spc_char/alpha.gif' border=0>-dialkylamino acid ester salts

1942-1944A simple and efficient sonochemical esterification of proteino­genic as well as cyclic ,-dialkyl amino acid methyl and ethyl ester hydrochloride salts employing thionyl chloride and alcohol has been reported. All the amino acid esters made have been obtained in good yield (94-98%) as pure compounds

Microwave irradiation accelerated rapid, efficient and high yield esterification of Boc-amino acid to Merrifield resin mediated by KF

1466-1469A rapid and efficient procedure for the attachment of Boc-amino acid to Merrifield resin in the presence of potassium fluoride by flash heating under microwave irradiation has been described. Esterification rate acceleration and higher loadings are obtained significantly. Also, reaction times are reduced from the conventional 24 hr to 5-6 min duration under microwave irradiation

Synthesis of Fmoc-protected <i style="">β</i>-amino alcohols and peptidyl alcohols from Fmoc-amino acid / peptide acid azides

1880-1886An efficient synthesis of N-9H-fluoren-9-ylmethoxycarbonyl(Fmoc)-β-amino alcohols by the reduction of Fmoc--amino acyl azides employing aqueous NaBH4 as a reducing agent has been described. The reduction is found to be simple and almost complete. All the Fmoc-β-amino alcohols prepared are fully characterized by 1H and 13C NMR and mass spectrometry. Further, the method is extended for the reduction of seven Fmoc-dipeptidyl acids to the corresponding alcohols. Their reduction is also found to be smooth and complete

Wolff rearrangement of <i>N^{<img src='/image/spc_char/alpha.gif' border=0>}</i>- Boc-/Z-protected aminodiazoketones to the corresponding <i>β</i>-amino acids under microwave irradiation<b style=""></b>

2611-2613The Wolff rearrangement of N-Boc-/Z-protected amino­diazoke­tones in the presence of silver benzoate under microwave irradiation is described. The reaction is found to be rapid, efficient and complete. It results in the isolation of Boc-/Z- protected-β-amino acids in good purity as well as yield

An efficient concomitant synthesis of <i>O</i>-succinimidyl-(9<i>H</i>-fluoren-9-yl methoxy carbonylamino)peptidyl carbamates and their application in the synthesis of oligo-<img src='/image/spc_char/alpha.gif' border=0>-peptidyl ureas

69-76 An efficient method for the synthesis of O-succinimidyl (9H-fluorene-9-yl methoxycarbonylamine) peptidyl carbamates from the corresponding N-Fmoc peptidyl isocyanates through the concomitant Curtius rearrangement of N-Fmoc peptidyl acid azide and coupling with N-hydroxysuccinimide is described. The introduction of urea moiety at various positions in peptidyl backbone of VALVAL hexapeptide sequence has been carried out by the fragment coupling using peptidyl carbamates. All the oligo--peptidyl ureas are isolated as crystalline solids in 80-85% yield and have been fully characterized by 1H and 13C NMR and mass spectrometry. </smarttagtype

Solid-state NMR at natural isotopic abundance for the determination of conformational polymorphism - the case of designed beta-turn peptides containing di-prolines

The proton double quantum-carbon single quantum correlation experiment has been applied to designed peptides in the solid state in natural isotopic abundance. Analogous to nOe studies in solution, through-space double-quantum connectivities have been exploited to obtain the cis-trans conformational polymorphism of diproline residues occurring at beta-turns in the peptides