In 2005, the ACS Green Chemistry Institute (GCI) and the global pharmaceutical corporations developed the ACS GCI Pharmaceutical Roundtable to encourage the integration of green chemistry and green engineering into the pharmaceutical industry. The Roundtable has developed a list of key research areas. The purpose of this perspective is to summarise how that list was agreed, provide an assessment of the current state of the art in those areas and to highlight areas for future improvement.

An improved and efficient bromination of 3,5-bis(trifluoromethyl)benzene was developed. A safe and reliable preparation of the potentially explosive 3,5-bis(trifluoromethyl)phenyl Grignard and 3-trifluoromethylphenyl Grignard reagents, from the precursor bromides, is described. Reaction System Screening Tool (RSST) and Differential Thermal Analysis (DTA) studies suggest these trifluoromethylphenyl Grignard reagents can detonate on loss of solvent contact or upon moderate heating. When prepared and handled according to the methods described herein, these Grignard reagents can be safely prepared and carried on to advanced intermediates.

The Heck-type arylation of alkenes was achieved in aqueous polyethylene glycol using a magnetically recoverable heterogenized palladium catalyst employing diaryliodonium salts under ambient conditions. The benign reaction medium and the stability of the catalyst are the salient features of this simple and facile protocol. † Electronic supplementary information (ESI) available: Experimental procedures, and 1 H and 13 C NMR spectra of all compounds are provided. See

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A total synthesis of the potent, naturally occurring immunomodulators (-)-rapamycin (1) and (-)-27demethoxyrapamycin (2) has been achieved via a unified, highly convergent synthetic strategy. Both targets were elaborated from common building blocks A-E, the latter available in decagram quantities. Herein we present the construction of the ABC northern perimeters of 1 and 2. The accompanying paper describes the preparation of the southern perimeter DE segment, triene and deprotection model studies, and completion of the synthetic venture. Notable features of the approach include stereoselective σ-bond constructions of trisubstituted olefins and the union of advanced intermediates via efficient dithiane couplings.In 1975, researchers at Ayerst Laboratories (Montréal, Canada) reported the discovery of rapamycin (1), an antibiotic produced by Streptomyces hydroscopicus (NRRL 5491) endemic to Easter Island soil samples. 1 Structure elucidation via degradation and X-ray crystallography revealed a fundamentally new type of macrocycle, a 31-membered ring containing both lactam and lactone linkages, 2 richly adorned with stereochemical and functional elements. Notwithstanding its challenging architecture, rapamycin attracted little interest until 1986, when the isolation of the structurally related immunosuppressant FK506 (3) 3 sparked investigations of the immunosuppressive activity of 1. Rapamycin proved to be a potent immunomodulator and prospective anti-graft-rejection agent. 4,5 In rats, 1 completely suppressed the development of cellular immunity as well as the formation of an IgE-like antibody. 6 Both rapamycin and FK506 bind to the cytosolic immunophilin FKBP12, a strict requirement for the observed physiological responses. 7 At this point, however, the immunosuppressive mechanisms diverge. The FK506-FKBP12 complex binds calcineurin, 8,9 whereas a different target for the rapamycin-FKBP12 complex has recently been identified and variously designated as mTOR, RAFT and FRAP. 10,11 Whereas the specific roles of 1 and its complexes in signal transduction and immunosuppression remain unclear, it has been established that rapamycin interferes with a Ca 2+ -independent signaling pathway emanating from the IL-2 receptor. 12 Whereas preliminary reports indicated that the naturally occurring congener 13 27-demethoxyrapamycin (2) is 10-fold less active than 1 in the mixed lymphocyte response assay, 2 is X Hatanaka, H.; Hashimoto, M.; Nishiyama, M.; Goto, T.; Okuhara, M.; Kohsaka, M.; Aoki, H.; Imanaka, H. J. Antibiot. 1987, 40, 1249. (4) (a) Luo, H.; Chen, H.; Daloze, P.; Chang, J. Y.; St-Louis, G.; Wu, J.