A one-pot synthesis of 2-dialkylamino-5,11-dimethyl-6H-pyrimido[5,4-b]carbazol-4(3H)-ones, as new ellipticine analogs, starting from aminocarbazole derivatives is reported. This method allowed us to prepare a library of potentially useful compounds in the pharmaceutical field.

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New substituted methyl thieno[3,4-c]cinnoline-3-carboxylate compounds were synthesized from the corresponding methyl 3-aminothiophene-2-carboxylate precursors by a new route using a modified Sandmeyer reaction. Under proper conditions, Sandmeyer reaction led to the formation of thieno[3,4-c] cinnoline compounds by a regioselective intramolecular cyclization, instead of the expected substitution of the amino group by a bromine atom

The evolution of salt tolerance is interesting for several reasons. First, since salt-tolerant plants (halophytes)
employ several different mechanisms to deal with salt, the evolution of salt tolerance represents a fascinating case study in the
evolution of a complex trait. Second, the diversity of mechanisms employed by halophytes, based on processescommonto all
plants, sheds light on the way that a plant’s physiology can become adapted to deal with extreme conditions. Third, as the
amount of salt-affected land increases around the globe, understanding the origins of the diversity of halophytes should
provide a basis for the use of novel species in bioremediation and conservation. In this reviewwepose the question,howmany
times has salt tolerance evolved since the emergence of the land plants some 450–470 million years ago? We summarise the
physiological mechanisms underlying salt-tolerance and provide an overview of the number and diversity of salt-tolerant
terrestrial angiosperms (defined as plants that survive to complete their life cycle in at least 200mM salt). We consider the
evolution of halophytes using information from fossils and phylogenies. Finally, we discuss the potential for halophytes to
contribute to agriculture and land management and ask why, when there are naturally occurring halophytes, it is proving
to be difficult to breed salt-tolerant crops

A highly sensitive and selective first-derivative spectrophotometric method has been developed for the determination
of aluminum and iron in mixtures. The method is based on the formation of the binary complexes
of aluminum and iron with Alizarin yellow R (AYR) 5-[4-nitrophenylazo]salicylic acid at pH 2.0 with molar
absorptivity of 1.1⋅104 l⋅mol–1⋅cm–1. A zero-crossing technique is found suitable for the direct measurement of
the first derivative value at the specified wavelength, so aluminum and iron were thus determined in the
ranges 1.3–5.4 μg/ml and 1.1–8.3 μg/ml, respectively, in the presence of both components. The detection limits
were found to be 1.4 ng/ml for aluminum and 2.8 ng/ml for iron. The relative standard deviations were in
all cases less than 1.5%. The proposed method was successfully applied for the simultaneous determination of
aluminum and iron in certified reference aluminum samples

A highly sensitive and selective first-derivative spectrophotometric method has been developed for the determination
of aluminum and iron in mixtures. The method is based on the formation of the binary complexes
of aluminum and iron with Alizarin yellow R (AYR) 5-[4-nitrophenylazo]salicylic acid at pH 2.0 with molar
absorptivity of 1.1⋅104 l⋅mol–1⋅cm–1. A zero-crossing technique is found suitable for the direct measurement of
the first derivative value at the specified wavelength, so aluminum and iron were thus determined in the
ranges 1.3–5.4 μg/ml and 1.1–8.3 μg/ml, respectively, in the presence of both components. The detection limits
were found to be 1.4 ng/ml for aluminum and 2.8 ng/ml for iron. The relative standard deviations were in
all cases less than 1.5%. The proposed method was successfully applied for the simultaneous determination of
aluminum and iron in certified reference aluminum samples

A highly sensitive and selective first-derivative spectrophotometric method has been developed for the determination
of aluminum and iron in mixtures. The method is based on the formation of the binary complexes
of aluminum and iron with Alizarin yellow R (AYR) 5-[4-nitrophenylazo]salicylic acid at pH 2.0 with molar
absorptivity of 1.1⋅104 l⋅mol–1⋅cm–1. A zero-crossing technique is found suitable for the direct measurement of
the first derivative value at the specified wavelength, so aluminum and iron were thus determined in the
ranges 1.3–5.4 μg/ml and 1.1–8.3 μg/ml, respectively, in the presence of both components. The detection limits
were found to be 1.4 ng/ml for aluminum and 2.8 ng/ml for iron. The relative standard deviations were in
all cases less than 1.5%. The proposed method was successfully applied for the simultaneous determination of
aluminum and iron in certified reference aluminum samples

A highly sensitive and selective first-derivative spectrophotometric method has been developed for the determination
of aluminum and iron in mixtures. The method is based on the formation of the binary complexes
of aluminum and iron with Alizarin yellow R (AYR) 5-[4-nitrophenylazo]salicylic acid at pH 2.0 with molar
absorptivity of 1.1⋅104 l⋅mol–1⋅cm–1. A zero-crossing technique is found suitable for the direct measurement of
the first derivative value at the specified wavelength, so aluminum and iron were thus determined in the
ranges 1.3–5.4 μg/ml and 1.1–8.3 μg/ml, respectively, in the presence of both components. The detection limits
were found to be 1.4 ng/ml for aluminum and 2.8 ng/ml for iron. The relative standard deviations were in
all cases less than 1.5%. The proposed method was successfully applied for the simultaneous determination of
aluminum and iron in certified reference aluminum samples

A facile, highly selective and sensitive
spectrophotometric method has been developed for
the determination of manganese (II) in different foods.
The method is based on the formation of the binary
complexes of manganese with Mordant brown 33 (MB33)
2, 4-diamino-5-(2-hydroxy-5-nitrophenylazo) benzene
sulfonic acid sodium salt at pH 9.0 with Tween 20 at
wavelengths 575 nm with molar absorbtivity 0.75×104
l mol-1 cm-1. Manganese was thus determined in the
ranges 1.1–4.4 μg mL-1 in the presence of Tween 20.
The detection limits were found to be 0.046 μg mL-1.
The effect of foreign ions was elucidated .The relative
standard deviations were in all instances less than 1.2
%. The proposed method was successfully applied for
the determination of manganese in different kinds of
foods.

A facile, highly selective and sensitive
spectrophotometric method has been developed for
the determination of manganese (II) in different foods.
The method is based on the formation of the binary
complexes of manganese with Mordant brown 33 (MB33)
2, 4-diamino-5-(2-hydroxy-5-nitrophenylazo) benzene
sulfonic acid sodium salt at pH 9.0 with Tween 20 at
wavelengths 575 nm with molar absorbtivity 0.75×104
l mol-1 cm-1. Manganese was thus determined in the
ranges 1.1–4.4 μg mL-1 in the presence of Tween 20.
The detection limits were found to be 0.046 μg mL-1.
The effect of foreign ions was elucidated .The relative
standard deviations were in all instances less than 1.2
%. The proposed method was successfully applied for
the determination of manganese in different kinds of
foods.