Convenient methods have been developed for the synthesis of derivatives of angular and linearpyrroloindoles. The first such method involves the bicyclization of m-phenylenebishydrazone of ethyl pyruvate in polyphosphates through the Fischer reaction with simultaneous formation of two pyrrole rings. The second method is based on attaching a pyrrole ring to an indoline molecule.Keywords: pyrroloindole, pyrroloindoline, m-phenylenebishydrazone of ethyl pyruvate, cyclization.Synthetic methods for pyrroloindoles now permit the preparation of similar bifunctional analogs of biologically active indole compounds [5]. Some of these compounds have bactericidal, antimicrobial, and antitumor properties [6][7][8]. The well-known natural antibiotic, CC-1065, which contains pyrroloindoline fragments, is many times more active than reported antitumor preparations [9]. Thus, the development of new synthetic methods and the synthesis of new pyrroloindole derivatives hold great interest.An angular isomer of diethoxycarbonylpyrroloindole 2 has been synthesized in 20% yield by the bicyclization of the m-phenylenebishydrazone of ethyl pyruvate (1) by heating this compound in 20% ethanolic HCl [10]. In our previous work [11], this yield was improved to 60% and compound 3, which is a linear isomer of diester 2, was obtained in 8% yield. The saponification of compounds 2 and 3 gave the corresponding diacids 4 and 5, whose decarboxylation led to angular and linear pyrroloindole isomers 6 and 7, respectively [10,11].In the present work, two methods are described for the synthesis of isomeric pyrroloindoles 6 and 7 and their derivatives, which we developed with the aim of increasing the yields of already reported and new compounds of this group.The first method is based on the abovementioned bicyclization of bishydrazone 1 according to the Fischer indole synthesis with the simultaneous formation of two pyrrole rings (Scheme 1), while the second involves the construction of a pyrrole ring in an indoline derivative (Scheme 2).Various condensing agents were studied as catalysts for the bicyclization of bishydrazone 1. Considerable tar formation occurs under rigorous conditions in the presence of ZnCl 2 , PPA, or AcOH/H 2 SO 4 . As noted above, the reaction in 20% ethanolic HCl is not very efficient [10]. A mixture of ethyl esters of PPA

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In the context of scalar QED we derive the pinch technique self-energies and vertices directly from the Schwinger-Dyson equations. After reviewing the perturbative construction, we discuss in detail the general methodology and the basic field-theoretic ingredients necessary for the completion of this task. The construction requires the simultaneous treatment of the equations governing the scalar self-energy and the fundamental interaction vertices. The resulting non-trivial rearrangement of terms generates dynamically the Schwinger-Dyson equations for the corresponding Green's functions of the background field method. The proof relies on the extensive use of the all-order Ward-identities satisfied by the full vertices of the theory and by the one-particle-irreducible kernels appearing in the usual skeleton expansion. The Ward identities for these latter quantities are derived formally, and several subtleties related to the structure of the multiparticle kernels are addressed. The general strategy for the generalization of the method in a non-Abelian context is briefly outlined, and some of the technical difficulties are discussed.

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