Valorization of Java citronella (Cymbopogon winterianus Jowitt) distillation waste as a potential source of phenolics/antioxidant: influence of extraction solvents.

Solid residues obtained after essential oil extraction from Cymbopogon winterianus Jowitt (Java citronella) was explored as a potential source of phenolics/antioxidant. Both the non-distilled plant materials and their solid residues were extracted with Soxhlet extraction method using solvents of various polarity viz. petroleum ether, chloroform, ethyl acetate, acetone, ethanol, methanol, water and various combination of (50% and 75%) of methanol, ethanol, and acetone in water. Different antioxidant assays like 2,2-diphenyl-1- picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide anion (SO) radical scavenging assay, ferric-reducing antioxidant power (FRAP) and iron chelating ability along with total phenol (TPC) and flavonoid content (TFC) was measured to evaluate the extract. Compared to distilled materials, the non-distilled plant materials had significantly higher TPC/TFC content and also exhibited higher antioxidant activities. 50% aqueous methanol showed the highest extractive yield, whereas 75% aqueous methanol exhibited the highest TPC and TFC content. The 50% or 75% aqueous methanolic extract also exhibited the highest DPPH, ABTS and SO scavenging activity and ferric-reducing antioxidant power activity. However, ethyl acetate and 75% aqueous acetone extract of non-distilled and distilled plant materials, respectively showed the highest iron chelating activity. The half maximal effective concentration (IC50 = µg/mL) for DPPH, ABTS, SO and metal chelating ability in non-distilled plant extract ranged from 64-387, 92-761, 285-870, and 164-924, respectively, and corresponding value of distilled materials ranged from 144-865, 239-792, 361-833 and 374-867, respectively. The EC50 (µg/mL) for FRAP assay ranged from 118-840 and 151-952 for non-distilled and distilled materials, respectively. The findings of this study indicate the potential of these by-products as a natural antioxidants source.

6-Meth-oxy-N-methyl-3-nitro-4-nitro-methyl-4H-chromen-2-amine.

In the title compound, C(12)H(13)N(3)O(6), the dihydro-pyran ring adopts a near screw-boat conformation. The dihedral angle between the mean planes of the benzene and dihydro-pyran rings is 6.35 (5)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) motif, which stabilizes the mol-ecular conformation. In the crystal, weak inter-molecular C-H⋯O, N-H⋯O and C-H⋯π hydrogen bonds contribute to the stabilization of the packing.

4-[4-(Diethyl-amino)-phen-yl]-N-methyl-3-nitro-4H-chromen-2-amine.

In the title compound, C(20)H(23)N(3)O(3), the dihydro-pyran ring adopts half-chair conformation. The chromene system makes a dihedral angle of 87.35 (5)° with the adjacent benzene ring. An intra-molecular N-H⋯O hydrogen bond generates an S(6) motif, which stabilizes the mol-ecular conformation. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds contribute to the stabilization of the packing.

5-(4-Chloro-phen-yl)-3-(2,4-dimethyl-thiazol-5-yl)-1,2,4-triazolo[3,4-a]isoquinoline.

In the title mol-ecule, C(21)H(15)ClN(4)S, the triazoloisoquinoline ring system is approximately planar, with an r.m.s. deviation of 0.054 (2) Šand a maximum deviation of 0.098 (2) Šfrom the mean plane for the triazole ring C atom that is bonded to the thia-zole ring. The thia-zole and benzene rings are twisted by 66.36 (7) and 56.32 (7)°, respectively, with respect to the mean plane of the triazoloisoquinoline ring system. In the crystal structure, mol-ecules are linked by inter-molecular C-H⋯N inter-actions along the a axis. The mol-ecular conformation is stabilized by a weak intra-molecular π-π inter-action involving the thia-zole and benzene rings, with a centroid-centroid distance of 3.6546 (11) Å. In addition, two other intermolecular π-π stacking inter-actions are observed, between the triazole and benzene rings and between the dihydro-pyridine and benzene rings [centroid-centroid distances = 3.6489 (11) and 3.5967 (10) Å, respectively].

5-(4-Chloro-phen-yl)-3-(2-fur-yl)-1,2,4-triazolo[3,4-a]isoquinoline.

In the title mol-ecule, C(20)H(12)ClN(3)O, the triazoloisoquinoline ring system is nearly planar, with an r.m.s. deviation of 0.018 (3) Šand a maximum deviation of 0.034 (3) Šfrom the mean plane for the triazole ring C atom which is bonded to the benzene ring. The furan and benzene rings are twisted by 59.71 (14) and 66.95 (10)°, respectively, with respect to the mean plane of the triazoloisoquinoline ring system. The mol-ecular conformation is stabilized by an intra-molecular π-π inter-action [centroid-to-centroid distance = 3.5262 (18) Å]. The crystal packing is stabilized by weak C-H⋯π inter-actions and weak π-π inter-actions [centroid-to-centroid distance = 3.9431 (17) Å].

4-(5-Phenyl-1,2,4-triazolo[3,4-a]isoquinolin-3-yl)benzonitrile.

In the title mol-ecule, C(23)H(14)N(4), the triazoloisoquinoline ring system is nearly planar, with an r.m.s. deviation of 0.038 (2) Šand a maximum deviation of -0.030 (2) Šfrom the mean plane of the triazole ring C atom which is bonded to the benzene ring. The benzene and phenyl rings are twisted by 57.65 (8) and 53.60 (9)°, respectively, with respect to the mean plane of the triazoloisoquinoline ring system. In the crystal structure, mol-ecules are linked by weak aromatic π-π inter-actions [centroid-centroid distance = 3.8074 (12) Å]. In addition, the crystal structure exhibits a nonclassical inter-molecular C-H⋯N hydrogen bond.

3-(4-Chloro-phen-yl)-5-phenyl-1,2,4-triazolo[3,4-a]isoquinoline.

In the title mol-ecule, C(22)H(14)ClN(3), the triazoloisoquinoline ring system is approximately planar, with an r.m.s. deviation of 0.033 (2) Šand a maximum departure from the mean plane of 0.062 (1) Šfor the triazole ring C atom, bonded to the benzene ring. The benzene and phenyl rings are twisted by 57.02 (6) and 62.16 (6)°, respectively, to the mean plane of the triazoloisoquinoline ring system. The mol-ecule is stabilized by a weak intra-molecular π-π inter-action [centroid-centroid distance = 3.7089 (10) Å] between the benzene and phenyl rings. In the crystal structure, weak inter-molecular C-H⋯N hydrogen bonds and C-H⋯π inter-actions link the mol-ecules.

3-tert-Butyl-1H-isochromene-1-thione.

The title compound, C(13)H(14)OS, crystallizes with two independent mol-ecules in the asymmetric unit. The unit cell contains three voids of 197 Å(3), but the residual electron density (highest peak = 0.24 e Å(-3) and deepest hole = -0.18 e Å(-3)) in the difference Fourier map suggests no solvent mol-ecule occupies this void. The crystal structure is stabilized by π-π inter-actions between the isocoumarin ring systems, with centroid-centroid distances of 3.6793 (14) and 3.6566 (15) Å.

3-Methyl-5-phenyl-1-(3-phenyl-isoquinolin-1-yl)-1H-pyrazole.

The title compound, C(25)H(19)N(3), is composed of an aryl-substituted pyrazole ring connected to an aryl-substituted isoquinoline ring system with a dihedral angle of 52.7 (1)° between the pyrazole ring and the isoquinoline ring system. The dihedral angle between the pyrazole ring and the phenyl ring attached to it is 27.4 (1)° and the dihedral angle between the isoquinoline ring system and the phenyl ring attached to it is 19.6 (1)°.

1-[3-(4-Chloro-phen-yl)isoquinolin-1-yl]-3,5-diphenyl-1H-pyrazole.

The title compound, C(30)H(20)ClN(3), is composed of a diaryl-substituted pyrazole ring connected to an aryl-substituted isoquinoline ring system with a dihedral angle of 65.1 (1)° between the pyrazole ring and the isoquinoline ring system. The 3-phenyl and 4-phenyl substitutents are twisted by 8.1 (1) and 43.0 (1)°, respectively, with respect to the pyrazole ring. The chloro-phenyl ring and the isoquinoline ring system are twisted by 21.2 (1)° with respect to each other.

1-[3-(4-Chloro-phen-yl)isoquinolin-1-yl]-3,5-diethyl-1H-pyrazole.

The title compound, C(22)H(20)ClN(3), is composed of a dialkyl-substituted pyrazole ring connected to an aryl-substituted isoquinoline ring system with a dihedral angle of 55.8 (1)° between the pyrazole ring and and the isoquinoline ring system. The dihedral angle between the chloro-phenyl ring and the isoquinoline ring system is 28.3 (1)°.

2-[2-(Hydroxy-meth-yl)phen-yl]-1-(1-naphth-yl)ethanol.

The mol-ecular conformation of the title compound, C(19)H(18)O(2), is stabilized by an intra-molecular O-H-O hydrogen bond. In addition, inter-molecular O-H-O inter-actions link the mol-ecules into zigzag chains running along the c axis.

5-Phenyl-3-(2-thien-yl)-1,2,4-triazolo[3,4-a]isoquinoline.

In the title mol-ecule, C(20)H(13)N(3)S, the triazoloisoquinoline ring system is approximately planar, with an r.m.s. deviation of 0.045 Šand a maximum deviation of 0.090 (2) Šfrom the mean plane for the triazole ring C atom which is bonded to the thio-phene ring. The phenyl ring is twisted by 52.0 (1)° with respect to the mean plane of the triazoloisoquinoline ring system. The thio-phene ring is rotationally disordered by approximately 180° over two sites, the ratio of refined occupancies being 0.73 (1):0.27 (1).

3-Benzyl-6-benzyl-amino-1-methyl-5-nitro-1,2,3,4-tetra-hydro-pyrimidine.

In the title compound, C(19)H(22)N(4)O(2), the tetra-hydro-pyrimidine ring adopts an envelope conformation (with the N atom connected to the benzyl group representing the flap). This benzyl group occupies a quasi-axial position. The two benzyl groups lie over the tetra-hydro-pyridimidine ring. The amino group is a hydrogen-bond donor to the nitro group.

1-(3,5-Diethyl-1H-pyrazol-1-yl)-3-phenyl-isoquinoline.

In the title mol-ecule, C(22)H(21)N(3), the isoquinoline ring is almost planar [maximum deviation = 0.046 (1) Å] and makes dihedral angles of 52.01 (4) and 14.61 (4)° with the pyrazole and phenyl rings, respectively. The phenyl ring and the pyrazole ring are twisted by 44.20 (6)° with respect to each other. The terminal C atoms of both of the ethyl groups attached to the pyrazole ring are disordered over two sites with occupancy ratios of 0.164 (7):0.836 (7) and 0.447 (16):0.553 (16). A weak intra-molecular C-H⋯N contact may influence the mol-ecular conformation. The crystal structure is stabilized by C-H⋯π contacts involving the phenyl and pyrazole rings, and by π-π stacking inter-actions involving the pyridine and benzene rings [centroid-centroid distance = 3.5972 (10) Å].

Identification of potential accessions of Asparagus racemosus for root yield and shatavarin IV content.

Successful restoration of over exploited species (Asparagus racemosus) depends upon variability, conservation and cultivation. Twelve elite accessions were characterized for fifteen quantitative and qualitative traits for sustainable cultivation and industrial uses. The evaluated accessions varied in morphology, herbage, root yield and shatavarin IV content. The accession DAR-7 was showing maximum herbage yield (1860 and 1850 g plant-1), fresh root weight (36.33 and 37.33 g plant-1), root girth (18.25 and 18.45 cm) and root yield (14.26 and 12.79 kg plant-1) in both the harvesting years. Shatavarin IV content in roots was maximum in DAR-14 (152.06 and 151.72 µg g-1), followed by DAR-28 (81.16 and 83.16 µg g-1). For economic yield accessions DAR-7, DAR-19, DAR-14, DAR-28 were found superior therefore, they may be further used in crop improvement program as valuable selection. In the cropping system they may act as a viable replacement of traditional crops viz., cumin, gram, cotton and groundnut. Asparagus cultivated under high density plantation ensured high economic return (Rs. 4.87 l ha-1year-1) with 3.66 B: C ratio, therefore, it could be considered a high returns substitute for traditional crops.

1-(4-Chloro-phen-yl)-2-phenyl-2-(3-phenyl-1-isoquinolylsulfan-yl)ethanone.

The title compound, C(29)H(20)ClNOS, is a 1-substituted-3-phenyl-isoquinoline that crystallizes with four independent mol-ecules in the asymmtric unit. The four mol-ecules have similar C-S-C angles. The most noteworthy differences between the mol-ecules relate to the inclination of the 3-phenyl subsituent with respect to the isoquinoline fused-ring [dihedral angles of 21.2 (1), 25.6 (2), 34.3 (1) and 36.5 (2)°].

2-[2-(Cyclo-hexyl-carbon-yl)phen-yl]-1-phenyl-ethanone.

The title diketone, C(21)H(22)O(2), features a phenyl-ene ring having benzoyl-methyl and cyclo-hexa-noyl substituents ortho to each other. The cyclo-hexyl ring adopts a chair conformation with the ketonic group occupying an equatorial position; the four-atom -C(O)-C ketonic unit is twisted out of the plane of the phenyl-ene ring by 34.9 (1)°.

1-(4-Chloro-phen-yl)-2-[(3-phenyl-isoquinolin-1-yl)sulfan-yl]ethanone.

The title compound, C(23)H(16)ClNOS, exhibits dihedral angles of 11.73 (1) and 66.07 (1)°, respectively, between the mean plane of the isoquinoline system and the attached phenyl ring, and between the isoquinoline system and the chloro-phenyl ring. The dihedral angle between the phenyl and chlorophenyl rings is 54.66 (1)°.

3-Phenyl-isoquinolin-1(2H)-one.

The title compound, C(15)H(11)NO, consists of a planar isoquinolinone group to which a phenyl ring is attached in a twisted fashion [dihedral angle = 39.44 (4)°]. The crystal packing is dominated by inter-molecular N-H⋯O and C-H⋯O hydrogen bonds which define centrosymmetric dimeric entitities.