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Self-immolative polymers (SIPs) are degradable polymers that have the ability to use a specific bond cleavage to initiate a cascade of reactions which ultimately result in complete depolymerization.[1] The cascade occurs from the polymer’s response to certain stimuli that selectively remove a stabilizing endcap of the polymer.[2] When the endcap is detached, elimination reactions of the polymer are initiated, which causes the SIP backbone to break down to smaller units. There has been an increasing interest in the therapeutic potential of benzimidazole-based compounds in anticancer drugs due to their high effectiveness and target specificity. Cancer cells generally disturb cell signalling pathways in the body, and current anticancer drugs act on these rapidly replicating cells with poor selectivity, which is why benzimidazole-based structures are of great interest in medicinal chemistry.[3]. Benzamidazoles are potentially useful in SIP applications because their multifunctional properties such as pH sensitivity and electron accepting ability would allow degradation under biocompatible conditions selective to targeted cells, potentially used as a drug delivery system. In this presentation I will discuss the Trant Team’s work on developing a benzimidazole-based SIP[4]. The polymers have been synthesized through the preparation of various starting materials and synthetic intermediates to produce two different benzimidazole derived self-immolative polymers. Along with the synthesis of such intermediates, spectroscopic techniques were applied to characterize and confirm the presence of each compound. This presentation will introduce the first known benzimidazole-backbone SIP created and discuss the synthesis and associated challenges of producing these materials during the COVID-19 pandemic. References: Sirianni, Q. E.A., Gillies, E. R. The Architectural Evolution of Self-Immolative Polymers. Polymer. 2020, 202, pp. 122638. Sagi, A., Weinstain, R., Karton, N., Shabat, D. Self-Immolative Polymers. J. Am. Chem. 2008, 130, pp. 5434-5435. Goud, N. A., Kumar, P., Bharath, R. D. Recent Developments of Target-Based Benzimidazole Derivatives as Potential Anticancer Agents. IntechOpen. 2022. Benzimidazole [Working Volume], pp. 1-18. Taimoory, S. Maryamdokht, Xiao Yu, John F. Trant. Highly optically responsive divalent benzimidazolium-based axles with pseudorotaxane potential. 2021.

Genus Mileewa Distant, 1908 Mileewa Distant, 1908, The Fauna of British India including Ceylon and Burma. Rhynchota IV Homoptera and Appendix (Pt.), 4: 238. Bolinlila Distant, 1910, Insecta Transvaaliensia, a contribution to knowledge of the entomology of South Africa, 10: 234. Tylozygoides Matsumura, 1912, Annotationes Zoologicae Japonenses, 8: 42. Faenius Distant, 1918, The Fauna of British India including Ceylon and Burma. Rhynchota VII Homoptera and Appendix (Pt.), 7: 14. Augulus Distant, 1918, The Fauna of British India including Ceylon and Burma. Rhynchota VII Homoptera and Appendix (Pt.), 7: 98. Formotettigella Ishihara, 1965, Special Bulletin of Lepidopterological Society of Japan, 1: 216. Dignosis. Small, slender, usually dark brown or black species, forewing often with transparent spots. Crown with ocelli situated medially, anterior margin rounded or produced. Frontoclypeus swollen. Pronotum broad and short, anterior margin arched, posterior margin concave or straight, lateral margin oblique straight. Forewing apical margin oblique and straight. Hindleg femoral setal formula 2:1:1. Male pygofer with ventral pygofer process, ventral margin bearing slender setae, apical margin occasionally with thick setae. Subgenital plates slender, with thick setae row, slender and short microsetae sometimes present. Connective Y-shaped, rarely V-shaped, triangular or trapezoid shaped. Style elongated, apex slender or sickle shaped. Aedeagus variously shaped., Published as part of Yu, Xiao-Fei, He, Hong-Li & Yang, Mao-Fa, 2021, Three new species of Mileewa (Hemiptera: Cicadellidae: Mileewinae) from Tibet China, pp. 435-443 in Zootaxa 4933 (3) on pages 435-436, DOI: 10.11646/zootaxa.4933.3.9, http://zenodo.org/record/4555123, {"references":["Distant, W. L. (1908) The Fauna of British India including Ceylon and Burma. Rhynchota IV Homoptera and Appendix (Pt.). Taylor & Francis, London, 501 pp.","Distant, W. L. (1910) Description of a new species of Cicadidae. Pomona Journal Entomology, 2, 346.","Matsumura, S. (1912) Die Cicadinen Japans II. Annotationes Zoologicae Japonenses, 8, 15 - 51.","Distant, W. L. (1918) The fauna of British India including Ceylon and Burma. Rhynchota VII, 1 - 109.","Ishihara, T. (1965) Some species of Formosan Homoptera. Special Bulletin of Lepidopterological Society of Japan, 1, 201 - 221."]}

Mileewa digitata sp. nov. (Figs 1���2) Length: ��4.2���4.6 mm, ♀ 4.6���4.7 mm. Coloration. Head, thorax and forewing black. Upper half of crown brownish (black in some males), bearing three yellowish longitudinal stripes and some irregular cloudy spots. Eyes and ocelli off-white. Scutellum yellow white in distal half, medium of basal half brown yellowish, with a distinct vertical line and two round black spots beside end of vertical line (thorax and scutellum totally black, without stripe in some males). Face, thorax in ventral view and legs yellow white, pretarsus black, abdomen yellowish ventrally, subgenital plates and pygofer dark brown. Forewing with scattered yellow-brown translucent spots in basal half, outer margin with transparent edge, posterior margin with two equirotal transparent markings at medium, distal area with two preapical crescent-shaped transparent markings. External features. Head anterior margin roundly produced in dorsal view, median length of crown equal to interocular width; ocelli located on line between anterior eye angles; lateral frontal suture extending onto crown and attaining ocelli; coronal suture reaching two-third median length of crown. Face with frontoclypeus moderately convex, muscle impressions distinct, anteclypeus longitudinally swollen, clypeal suture obscure. Male genitalia. Male pygofer trapezoidal in lateral view, dorsal margin straight, surface with few microsetae, ventral process slender not reaching posterior margin, curved dorsad. Anal tube appendage absent. Subgenital plates longer than pygofer, surface bearing biserial macrosetae and slender and short setae from basal 1/4 to apex. Connective trapezoidal, longer than wide. Style slender, apex with finger-like process directed dorsad, with few teeth. Aedeagus elongate, preatrium absent, dorsal apodeme developed, aedeagal shaft sinuate in lateral view, with numerous denticule in distal half, apex either with two long processes directed basad, five small asymmetric processes or a few teeth (see Remarks); gonopore preapical on posterior surface. Etymology. The specific epithet is derived from the Latin word digitus meaning finger-like, referring to the finger-like process of the style. Material examined. Holotype ��, China: Tibet, Motuo, Beibeng, 1 August 2020, coll. Xiaofei Yu & Zaihua Yang. Paratypes: 2����, 18♀♀, the same data as holotype; 23����, 56♀♀, China: Tibet, Motuo, 27���31 July 2020, coll. Xiaofei Yu & Fangling Xu; 10����, 7♀♀, China: Tibet, Motuo, Beibeng, 1���3 August 2020, lighted by Xiaofei Yu; 1��, 4♀♀, China: Tibet, Motuo, Beibeng, 13 August 2020, coll. Xianyi Wang; 3����, 6♀♀, China: Tibet, Motuo, Dexing (1068 m), 15 August 2020, coll. Xianyi Wang. (GUGC). Remarks. This species is very similar to Mileewa octospina Yang, 2010 in external morphological characteristics, but differs from the later in having the ventral pygofer process very slender and apical processes of the aedeagus extended laterad. The variation found in the apex of the aedeagus, i.e., either with two long symmetrical processes, five small asymmetric processes or a few teeth, is treated as intraspecific., Published as part of Yu, Xiao-Fei, He, Hong-Li & Yang, Mao-Fa, 2021, Three new species of Mileewa (Hemiptera: Cicadellidae: Mileewinae) from Tibet China, pp. 435-443 in Zootaxa 4933 (3) on page 436, DOI: 10.11646/zootaxa.4933.3.9, http://zenodo.org/record/4555123, {"references":["Yang, M. F., Meng, Z. H. & Li, Z. Z. (2010) Five new species of the genus Mileewa from Yunnan, China (Homoptera, Cicadellidae, Cicadellinae). Acta Zootaxonomica Sinica, 35, 892 - 901."]}

Mileewa nigricincta sp. nov. (Figs 5���6) Length: �� 4.8 mm, ♀ 4.4���4.8 mm. Coloration. Head and thorax bright yellowish dorsally, eyes black. Face, thorax ventrally, legs and abdomen ventrally off-white, face apically, tibia and pygofer yellow. Forewing yellow-white basally, anterior and apical margins black; apically with two oval yellow-pale transparent large spots. External features. Crown distinctly produced, median length slightly greater than interocular width; crown slightly swollen, shallowly concave at ocelli; ocelli located on line between anterior eye angles and end of lateral frontal sutures; coronal suture reaching half median length of crown. Face with frontoclypeus slightly convex, muscle impressions obscure; anteclypeus longitudinally convex, apical margin slightly reflexed, clypeal suture distinct. Male genitalia. Male pygofer in lateral view with dorsal and ventral margins nearly straight, ventral margin with small setae, ventral process long not beyond posterior margin, curved dorsad, apex branched with longer branch darkly pigmented. Anal tube appendage absent. Subgenital plates extending posteriorly beyond pygofer apex, surface with macrosetae on inner margin from basal 1/3 to apex, with long or short microsetae. Connective Y-shaped, longer than wide, stem slender, lateral arms short and broad. Style slender, with small setae near apical one-third, without teeth, apex abruptly twisted laterally. Aedeagus with preatrium nearly quarter length of shaft; dorsal apodeme weakly developed, shaft in lateral view moderately broad, sinuate, apex with pair of robust tapered processes extended ventrad and basad but not divergent from each other in ventral view; gonopore preapical on posterior surface at base of processes. Etymology. The specific name refers to the brown margin of the forewing. Material examined. Holotype ��, China: Tibet, Motuo, Dexing (1068 m), 15 August 2020, coll. Xianyi Wang. Paratypes: 1♀, Tibet, Motuo, 29 July 2020, coll. Xiaofei Yu; 2♀♀, China: Yunnan, Tengchong, Shangyun (1700��� 1900 m), 15 July 2002, coll. Maofa Yang (GUGC). Remarks. This new species can be easily distinguished from the other species of the genus by its unusual coloration and shape of the male genitalia., Published as part of Yu, Xiao-Fei, He, Hong-Li & Yang, Mao-Fa, 2021, Three new species of Mileewa (Hemiptera: Cicadellidae: Mileewinae) from Tibet China, pp. 435-443 in Zootaxa 4933 (3) on pages 442-443, DOI: 10.11646/zootaxa.4933.3.9, http://zenodo.org/record/4555123

Mileewa furcata sp. nov. (Figs 3���4) Length: ��3.8 mm, ♀ 3.9 mm. Coloration. Head and thorax black in dorsal view, eyes black. Face and forewing black. Thorax, legs and abdomen ventrally off-white. Subgenital plates and pygofer black. External features. Crown with anterior margin broadly rounded in dorsal view, median length about equal to interocular width; ocelli located on line between anterior eye angles; lateral frontal suture extending onto crown and attaining ocelli; coronal suture almost reaching 1/2 median length of crown. Face with frontoclypeus weakly convex, muscle impressions distinct; anteclypeus longitudinally convex, flat apically, clypeal suture obscure. Male genitalia. Male pygofer nearly triangular in lateral view, ventral margin bearing few microsetae; ventral process well developed, with elongate supbapical spine directed dorsad. Anal tube appendage absent. Subgenital plates narrow, extended to posterior margin of pygofer, surface with uniseriate macrosetae on inner margin, some long microsetae dispersed on distal one-fourth. Connective longer than wide with stem long, lateral arms short and median anterior lobe quadrate. Style slender, with microsetae near middle and small lateral tooth near distal onethird. Aedeagus with preatrium quarter length of shaft, dorsal apodeme short, apex thin with expanded subapical in-curled lateral margins and a pair of branched apical processes; gonopore apical between bases of processes. Etymology. The species name, a Latin adjective, refers to the branched or furcate aedeagal processes. Material examined. Holotype: ��, China: Tibet, Motuo, 1 August 2020, coll. Xiaofei Yu & Zaihua Yang. Paratypes: 1♀, the same data as holotype (GUGC). Remarks. This new species is similar to Mileewa yigongana Yang, 2005 in external morphological characteristics, but can be readily distinguished from the later by the black scutellum apex (scutellum apex yellow-white in M. yigongana), black face with only anteclypeus apex off-white (frontoclypeus yellow-white except base black in M. yigongana), and the shape of the male ventral pygofer process, subgenital plates and aedeagus., Published as part of Yu, Xiao-Fei, He, Hong-Li & Yang, Mao-Fa, 2021, Three new species of Mileewa (Hemiptera: Cicadellidae: Mileewinae) from Tibet China, pp. 435-443 in Zootaxa 4933 (3) on pages 438-440, DOI: 10.11646/zootaxa.4933.3.9, http://zenodo.org/record/4555123, {"references":["Yang, M. F. & Song, D. M. (2005) Two new species of Cicadellinae (Hemiptera, Cicadellidae) from Xizang, China. Entomotaxonomia, 27, 97 - 102."]}